User:The Transhumanist
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Introduction
Hi. My name is The Transhumanist.
I love emerging and evolving technologies, and so... I'm currently immersed in studying AI (particularly generative AI and reasoning engines), and big data. I dabble in JavaScript, including writing user scripts from time to time. My best user script so far, is SearchSuite... SearchSuite provides further control over Wikipedia search results, such as on/off features to sort them, to present results one-per-line, and more. While it seems to work fairly well, there is definitely room for improvement. Comments and suggestions are welcome. By the way, most of the scripts I've been working on are for building and augmenting outlines...
I'm interested in all knowledge, especially how to organize it so you can find whatever is most relevant at any given moment. I've been around Wikipedia since the Fall of 2005, and have been working mostly on Wikipedia's structure, and its knowledge navigation systems, throughout that time. |
Selected articles that I've worked on
- Image 1Types of democracy refers to the various governance structures that embody the principles of democracy ("rule by the people") in some way. Democracy is frequently applied to governments (ranging from local to global), but may also be applied to other constructs like workplaces, families, community associations, and so forth.
Types of democracy can cluster around values. Some such types, defined as direct democracy (or participatory democracy, or deliberative democracy), promote equal and direct participation in political decisions by all members of the public. Others, including the many variants of representative democracy, favor more indirect or procedural approaches to collective self-governance, where decisions are made by elected representatives rather than by the people directly.
Types of democracy can be found across time, space, and language. The foregoing examples are just a few of the thousands of refinements of, and variations on, the central notion of "democracy." (Full article...) - Image 2A userscript manager is a type of browser extension and augmented browsing technology that provides a user interface to manage userscripts. The main purpose of a userscript manager is to execute scripts on webpages as they are loaded. The most common operations performed by a userscript manager include creating, installing, organizing, deleting and editing scripts, as well as modifying script permissions (e.g. website exceptions).
Userscript managers use metadata that is embedded in a script's source code primarily to determine the websites it should execute on and the dependencies necessary for the script to run properly. Metadata can also include information that is useful to the user such as the script's name, author, description and version number. (Full article...) - Image 3Prehistoric technology is technology that predates recorded history. History is the study of the past using written records. Anything prior to the first written accounts of history is prehistoric, including earlier technologies. About 2.5 million years before writing was developed, technology began with the earliest hominids who used stone tools, which they first used to hunt food, and later to cook.
There are several factors that made the evolution of prehistoric technology possible or necessary. One of the key factors is behavioral modernity of the highly developed brain of Homo sapiens capable of abstract reasoning, language, introspection, and problem-solving. The advent of agriculture resulted in lifestyle changes from nomadic lifestyles to ones lived in homes, with domesticated animals, and land farmed using more varied and sophisticated tools. Art, architecture, music and religion evolved over the course of the prehistoric periods. (Full article...) - Image 4Artificial general intelligence (AGI) is a type of artificial intelligence (AI) that matches or surpasses human capabilities across a wide range of cognitive tasks. This is in contrast to narrow AI, which is designed for specific tasks. AGI is considered one of various definitions of strong AI.
Creating AGI is a primary goal of AI research and of companies such as OpenAI, DeepMind, and Anthropic. A 2020 survey identified 72 active AGI R&D projects spread across 37 countries.
The timeline for achieving AGI remains a subject of ongoing debate among researchers and experts. , some argue that it may be possible in years or decades; others maintain it might take a century or longer; and a minority believe it may never be achieved. There is debate on the exact definition of AGI, and regarding whether modern large language models (LLMs) such as GPT-4 are early, incomplete forms of AGI. AGI is a common topic in science fiction and futures studies.
Contention exists over the potential for AGI to pose a threat to humanity; for example, OpenAI claims to treat it as an existential risk, while others find the development of AGI to be too remote to present a risk. (Full article...) - Image 5This glossary of philosophy is a list of definitions of terms and concepts relevant to philosophy and related disciplines, including logic, ethics, and theology. (Full article...)
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Cardiology (from Ancient Greek καρδίᾱ (kardiā) 'heart', and -λογία (-logia) 'study') is the study of the heart. Cardiology is a branch of medicine that deals with disorders of the heart and the cardiovascular system. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease, and electrophysiology. Physicians who specialize in this field of medicine are called cardiologists, a sub-specialty of internal medicine. Pediatric cardiologists are pediatricians who specialize in cardiology. Physicians who specialize in cardiac surgery are called cardiothoracic surgeons or cardiac surgeons, a specialty of general surgery. (Full article...) - Image 7Automatic taxonomy construction (ATC) is the use of software programs to generate taxonomical classifications from a body of texts called a corpus. ATC is a branch of natural language processing, which in turn is a branch of artificial intelligence.
A taxonomy (or taxonomical classification) is a scheme of classification, especially, a hierarchical classification, in which things are organized into groups or types. Among other things, a taxonomy can be used to organize and index knowledge (stored as documents, articles, videos, etc.), such as in the form of a library classification system, or a search engine taxonomy, so that users can more easily find the information they are searching for. Many taxonomies are hierarchies (and thus, have an intrinsic tree structure), but not all are.
Manually developing and maintaining a taxonomy is a labor-intensive task requiring significant time and resources, including familiarity of or expertise in the taxonomy's domain (scope, subject, or field), which drives the costs and limits the scope of such projects. Also, domain modelers have their own points of view which inevitably, even if unintentionally, work their way into the taxonomy. ATC uses artificial intelligence techniques to quickly automatically generate a taxonomy for a domain in order to avoid these problems and remove limitations. (Full article...) - Image 8
The afterlife or life after death is a purported existence in which the essential part of an individual's stream of consciousness or identity continues to exist after the death of their physical body. The surviving essential aspect varies between belief systems; it may be some partial element, or the entire soul or spirit, which carries with it one's personal identity.
In some views, this continued existence takes place in a spiritual realm, while in others, the individual may be reborn into this world and begin the life cycle over again, known as reincarnation, likely with no memory of what they have done in the past. In this latter view, such rebirths and deaths may take place over and over again continuously until the individual gains entry to a spiritual realm or otherworld. Major views on the afterlife derive from religion, esotericism and metaphysics.
Some belief systems, such as those in the Abrahamic tradition, hold that the dead go to a specific place (e.g. Paradise or Hell) after death, as determined by their God, based on their actions and beliefs during life. In contrast, in systems of reincarnation, such as those in the Indian religions, the nature of the continued existence is determined directly by the actions of the individual in the ended life. (Full article...) - Image 9This article explains terms used for the British Armed Forces' ordnance (weapons) and ammunition. The terms may have different meanings depending on its usage in another country's military. (Full article...)
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Compliant bonding is used to connect gold wires to electrical components such as integrated circuit "chips". It was invented by Alexander Coucoulas in the 1960s. The bond is formed well below the melting point of the mating gold surfaces and is therefore referred to as a solid-state type bond. The compliant bond is formed by transmitting heat and pressure to the bond region through a relatively thick indentable or compliant medium, generally an aluminum tape (Figure 1). (Full article...) - Image 11
Information science is an academic field which is primarily concerned with analysis, collection, classification, manipulation, storage, retrieval, movement, dissemination, and protection of information. Practitioners within and outside the field study the application and the usage of knowledge in organizations in addition to the interaction between people, organizations, and any existing information systems with the aim of creating, replacing, improving, or understanding the information systems.
Historically, information science (informatics) is associated with computer science, data science, psychology, technology, library science, healthcare, and intelligence agencies. However, information science also incorporates aspects of diverse fields such as archival science, cognitive science, commerce, law, linguistics, museology, management, mathematics, philosophy, public policy, and social sciences. (Full article...) - Image 12
Ceramic art is art made from ceramic materials, including clay. It may take varied forms, including artistic pottery, including tableware, tiles, figurines and other sculpture. As one of the plastic arts, ceramic art is a visual art. While some ceramics are considered fine art, such as pottery or sculpture, most are considered to be decorative, industrial or applied art objects. Ceramic art can be created by one person or by a group, in a pottery or a ceramic factory with a group designing and manufacturing the artware.
In Britain and the United States, modern ceramics as an art took its inspiration in the early twentieth century from the Arts and Crafts movement, leading to the revival of pottery considered as a specifically modern craft. Such crafts emphasized traditional non-industrial production techniques, faithfulness to the material, the skills of the individual maker, attention to utility, and an absence of excessive decoration that was typical to the Victorian era.
The word "ceramics" comes from the Greek keramikos (κεραμεικός), meaning "pottery", which in turn comes from keramos (κέραμος) meaning "potter's clay". Most traditional ceramic products were made from clay (or clay mixed with other materials), shaped and subjected to heat, and tableware and decorative ceramics are generally still made this way. In modern ceramic engineering usage, ceramics is the art and science of making objects from inorganic, non-metallic materials by the action of heat. It excludes glass and mosaic made from glass tesserae.
There is a long history of ceramic art in almost all developed cultures, and often ceramic objects are all the artistic evidence left from vanished cultures, like that of the Nok in Africa over 2,000 years ago. Cultures especially noted for ceramics include the Chinese, Cretan, Greek, Persian, Mayan, Japanese, and Korean cultures, as well as the modern Western cultures. (Full article...) - Image 13
Trichophyton is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are molds characterized by the development of both smooth-walled macro- and microconidia. Macroconidia are mostly borne laterally directly on the hyphae or on short pedicels, and are thin- or thick-walled, clavate to fusiform, and range from 4 to 8 by 8 to 50 μm in size. Macroconidia are few or absent in many species. Microconidia are spherical, pyriform to clavate or of irregular shape, and range from 2 to 3 by 2 to 4 μm in size. (Full article...) - Image 14The history of California can be divided into the Native American period (about 10,000 years ago until 1542), the European exploration period (1542–1769), the Spanish colonial period (1769–1821), the Mexican period (1821–1848), and United States statehood (September 9, 1850–present). California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. After contact with, many of the Native Americans died from foreign diseases. Finally, in the 19th century there was a genocide by United States government and private citizens, which is known as the California genocide.
After the Portolá expedition of 1769–1770, Spanish missionaries began setting up 21 California missions on or near the coast of Alta (Upper) California, beginning with the Mission San Diego de Alcala near the location of the modern day city of San Diego, California. During the same period, Spanish military forces built several forts (presidios) and three small towns (pueblos). Two of the pueblos would eventually grow into the cities of Los Angeles and San Jose. After Mexico's Independence was won in 1821, California fell under the jurisdiction of the First Mexican Empire. Fearing the influence of the Roman Catholic church over their newly independent nation, the Mexican government closed all of the missions and nationalized the church's property. They left behind a "Californio" population of several thousand families, with a few small military garrisons. After the Mexican–American War of 1846–1848, The Mexican Republic was forced to relinquish any claim to California to the United States.
The California Gold Rush of 1848–1855 attracted hundreds of thousands of ambitious young people from around the world. Only a few struck it rich, and many returned home disappointed. Most appreciated the other economic opportunities in California, especially in agriculture, and brought their families to join them. California became the 31st U.S. state in the Compromise of 1850 and played a small role in the American Civil War. Chinese immigrants increasingly came under attack from nativists; they were forced out of industry and agriculture and into Chinatowns in the larger cities. As gold petered out, California increasingly became a highly productive agricultural society. The coming of the railroads in 1869 linked its rich economy with the rest of the nation, and attracted a steady stream of settlers. In the late 19th century, Southern California, especially Los Angeles, started to grow rapidly. (Full article...) - Image 15Web scraping, web harvesting, or web data extraction is data scraping used for extracting data from websites. Web scraping software may directly access the World Wide Web using the Hypertext Transfer Protocol or a web browser. While web scraping can be done manually by a software user, the term typically refers to automated processes implemented using a bot or web crawler. It is a form of copying in which specific data is gathered and copied from the web, typically into a central local database or spreadsheet, for later retrieval or analysis.
Scraping a web page involves fetching it and extracting from it. Fetching is the downloading of a page (which a browser does when a user views a page). Therefore, web crawling is a main component of web scraping, to fetch pages for later processing. Once fetched, extraction can take place. The content of a page may be parsed, searched and reformatted, and its data copied into a spreadsheet or loaded into a database. Web scrapers typically take something out of a page, to make use of it for another purpose somewhere else. An example would be finding and copying names and telephone numbers, companies and their URLs, or e-mail addresses to a list (contact scraping).
As well as contact scraping, web scraping is used as a component of applications used for web indexing, web mining and data mining, online price change monitoring and price comparison, product review scraping (to watch the competition), gathering real estate listings, weather data monitoring, website change detection, research, tracking online presence and reputation, web mashup, and web data integration.
Web pages are built using text-based mark-up languages (HTML and XHTML), and frequently contain a wealth of useful data in text form. However, most web pages are designed for human end-users and not for ease of automated use. As a result, specialized tools and software have been developed to facilitate the scraping of web pages. (Full article...) - Image 16
Robotics is the interdisciplinary study and practice of the design, construction, operation, and use of robots.
Within mechanical engineering, robotics is the design and construction of the physical structures of robots, while in computer science, robotics focuses on robotic automation algorithms. Other disciplines contributing to robotics include electrical, control, software, information, electronic, telecommunication, computer, mechatronic, and materials engineering.
The goal of most robotics is to design machines that can help and assist humans. Many robots are built to do jobs that are hazardous to people, such as finding survivors in unstable ruins, and exploring space, mines and shipwrecks. Others replace people in jobs that are boring, repetitive, or unpleasant, such as cleaning, monitoring, transporting, and assembling. Today, robotics is a rapidly growing field, as technological advances continue; researching, designing, and building new robots serve various practical purposes. (Full article...) - Image 17Artificial consciousness (AC), also known as machine consciousness (MC), synthetic consciousness or digital consciousness, is the consciousness hypothesized to be possible in artificial intelligence. It is also the corresponding field of study, which draws insights from philosophy of mind, philosophy of artificial intelligence, cognitive science and neuroscience. The same terminology can be used with the term "sentience" instead of "consciousness" when specifically designating phenomenal consciousness (the ability to feel qualia).
Some scholars believe that consciousness is generated by the interoperation of various parts of the brain; these mechanisms are labeled the neural correlates of consciousness or NCC. Some further believe that constructing a system (e.g., a computer system) that can emulate this NCC interoperation would result in a system that is conscious. (Full article...) - Image 18In futures studies and the history of technology, accelerating change is the observed exponential nature of the rate of technological change in recent history, which may suggest faster and more profound change in the future and may or may not be accompanied by equally profound social and cultural change. (Full article...)
- Image 19Life extension is the concept of extending the human lifespan, either modestly through improvements in medicine or dramatically by increasing the maximum lifespan beyond its generally-settled biological limit of around 125 years. Several researchers in the area, along with "life extensionists", "immortalists", or "longevists" (those who wish to achieve longer lives themselves), postulate that future breakthroughs in tissue rejuvenation, stem cells, regenerative medicine, molecular repair, gene therapy, pharmaceuticals, and organ replacement (such as with artificial organs or xenotransplantations) will eventually enable humans to have indefinite lifespans through complete rejuvenation to a healthy youthful condition (agerasia). The ethical ramifications, if life extension becomes a possibility, are debated by bioethicists.
The sale of purported anti-aging products such as supplements and hormone replacement is a lucrative global industry. For example, the industry that promotes the use of hormones as a treatment for consumers to slow or reverse the aging process in the US market generated about $50 billion of revenue a year in 2009. The use of such hormone products has not been proven to be effective or safe. (Full article...) - Image 20Knowledge extraction is the creation of knowledge from structured (relational databases, XML) and unstructured (text, documents, images) sources. The resulting knowledge needs to be in a machine-readable and machine-interpretable format and must represent knowledge in a manner that facilitates inferencing. Although it is methodically similar to information extraction (NLP) and ETL (data warehouse), the main criterion is that the extraction result goes beyond the creation of structured information or the transformation into a relational schema. It requires either the reuse of existing formal knowledge (reusing identifiers or ontologies) or the generation of a schema based on the source data.
The RDB2RDF W3C group is currently standardizing a language for extraction of resource description frameworks (RDF) from relational databases. Another popular example for knowledge extraction is the transformation of Wikipedia into structured data and also the mapping to existing knowledge (see DBpedia and Freebase). (Full article...) - Image 21Existential risk from artificial general intelligence refers to the idea that substantial progress in artificial general intelligence (AGI) could lead to human extinction or an irreversible global catastrophe.
One argument supporting this risk suggests that human beings dominate other species because the human brain possesses distinctive capabilities other animals lack. If AI were to surpass human intelligence and become superintelligent, it might become uncontrollable. Just as the fate of the mountain gorilla depends on human goodwill, the fate of humanity could depend on the actions of a future machine superintelligence.
The plausibility of existential catastrophe due to AI is widely debated. It hinges in part on whether AGI or superintelligence are achievable, the speed at which dangerous capabilities and behaviors emerge, and whether practical scenarios for AI takeovers exist. Concerns about superintelligence have been voiced by leading computer scientists and tech CEOs such as Geoffrey Hinton, Yoshua Bengio, Alan Turing, Elon Musk, and OpenAI CEO Sam Altman. In 2022, a survey of AI researchers with a 17% response rate found that the majority believed there is a 10 percent or greater chance that our inability to control AI will cause an existential catastrophe. In 2023, hundreds of AI experts and other notable figures signed a statement declaring that "Mitigating the risk of extinction from AI should be a global priority alongside other societal-scale risks such as pandemics and nuclear war". Following increased concern over AI risks, government leaders such as United Kingdom prime minister Rishi Sunak and United Nations Secretary-General António Guterres called for an increased focus on global AI regulation.
Two sources of concern stem from the problems of AI control and alignment: controlling a superintelligent machine or instilling it with human-compatible values may be difficult. Many researchers believe that a superintelligent machine would likely resist attempts to disable it or change its goals, as that would prevent it from accomplishing its present goals. It would be extremely challenging to align a superintelligence with the full breadth of significant human values and constraints. In contrast, skeptics such as computer scientist Yann LeCun argue that superintelligent machines will have no desire for self-preservation. (Full article...) - Image 22Health has a variety of definitions, which have been used for different purposes over time. Health can be promoted by encouraging healthful activities, such as regular physical exercise and adequate sleep, and by reducing or avoiding unhealthful activities or situations, such as smoking or excessive stress. Some factors affecting health are due to individual choices, such as whether to engage in a high-risk behavior, while others are due to structural causes, such as whether the society is arranged in a way that makes it easier or harder for people to get necessary healthcare services. Still, other factors are beyond both individual and group choices, such as genetic disorders. (Full article...)
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- Image 24Ontology learning (ontology extraction, ontology generation, or ontology acquisition) is the automatic or semi-automatic creation of ontologies, including extracting the corresponding domain's terms and the relationships between the concepts that these terms represent from a corpus of natural language text, and encoding them with an ontology language for easy retrieval. As building ontologies manually is extremely labor-intensive and time-consuming, there is great motivation to automate the process.
Typically, the process starts by extracting terms and concepts or noun phrases from plain text using linguistic processors such as part-of-speech tagging and phrase chunking. Then statistical
or symbolic
techniques are used to extract relation signatures, often based on pattern-based or definition-based hypernym extraction techniques. (Full article...) - Image 25
A meal is an eating occasion that takes place at a certain time and includes consumption of food. The names used for specific meals in English vary, depending on the speaker's culture, the time of day, or the size of the meal.
Although they can be eaten anywhere, meals typically take place in homes, restaurants, and cafeterias. Regular meals occur on a daily basis, typically several times a day. Special meals are usually held in conjunction with such occasions as birthdays, weddings, anniversaries, and holidays. A meal is different from a snack in that meals are generally larger, more varied, and more filling than snacks.
The type of food that is served or consumed at any given time depends on regional customs. Three main meals are often eaten in the morning, early afternoon, and evening in most modern civilizations. Further, the names of meals are often interchangeable by custom as well. Some serve dinner as the main meal at midday, with supper as the late afternoon/early evening meal; while others may call their midday meal lunch and their early evening meal supper or dinner. Except for "breakfast," these names can vary from region to region or even from family to family. (Full article...)
Selected emerging technologies and related articles
- Image 1Finance is the study and discipline of money, currency and capital assets.
It is related to but distinct from economics, which is the study of the production, distribution, and consumption of goods and services.
Based on the scope of financial activities in financial systems, the discipline can be divided into personal, corporate, and public finance.
In these financial systems, assets are bought, sold, or traded as financial instruments, such as currencies, loans, bonds, shares, stocks, options, futures, etc. Assets can also be banked, invested, and insured to maximize value and minimize loss. In practice, risks are always present in any financial action and entities. (Full article...) - Image 2
Technology readiness levels (TRLs) are a method for estimating the maturity of technologies during the acquisition phase of a program. TRLs enable consistent and uniform discussions of technical maturity across different types of technology. TRL is determined during a technology readiness assessment (TRA) that examines program concepts, technology requirements, and demonstrated technology capabilities. TRLs are based on a scale from 1 to 9 with 9 being the most mature technology.
TRL was developed at NASA during the 1970s. The US Department of Defense has used the scale for procurement since the early 2000s. By 2008 the scale was also in use at the European Space Agency (ESA).
The European Commission advised EU-funded research and innovation projects to adopt the scale in 2010. TRLs were consequently used in 2014 in the EU Horizon 2020 program. In 2013, the TRL scale was further canonized by the International Organization for Standardization (ISO) with the publication of the ISO 16290:2013 standard. (Full article...) - Image 3Strategies for engineered negligible senescence (SENS) is a range of proposed regenerative medical therapies, either planned or currently in development, for the periodic repair of all age-related damage to human tissue. These therapies have the ultimate aim of maintaining a state of negligible senescence in patients and postponing age-associated disease. SENS was first defined by British biogerontologist Aubrey de Grey. Many mainstream scientists believe that it is a fringe theory. De Grey later highlighted similarities and differences of SENS to subsequent categorization systems of the biology of aging, such as the highly influential Hallmarks of Aging published in 2013.
While some biogerontologists support the SENS program, others contend that the ultimate goals of de Grey's programme are too speculative given the current state of technology. The 31-member Research Advisory Board of de Grey's SENS Research Foundation have signed an endorsement of the plausibility of the SENS approach. (Full article...) - Image 4
Space-based solar power (SBSP, SSP) is the concept of collecting solar power in outer space with solar power satellites (SPS) and distributing it to Earth. Its advantages include a higher collection of energy due to the lack of reflection and absorption by the atmosphere, the possibility of very little night, and a better ability to orient to face the Sun. Space-based solar power systems convert sunlight to some other form of energy (such as microwaves) which can be transmitted through the atmosphere to receivers on the Earth's surface.
Various SBSP proposals have been researched since the early 1970s, but as of 2014[update] none is economically viable with the space launch costs. Some technologists propose lowering launch costs with space manufacturing or with radical new space launch technologies other than rocketry. (Full article...) - Image 5Prosthetics, the artificial replacement of organic limbs or organs, often play a role in fiction, particularly science fiction, as either plot points or to give a character a beyond normal appearance. Numerous works of literature, television, and films feature characters who have prosthetics attached.
Prosthetics are used, in a narrative sense, to either, provide a plot point in the characters back-story, a plot point to give to character a disability (or more often in Science fiction, an advantage), or just to distinguish the character in some way. Having a character in a story with a prostheses, can sometimes be the whole point of the story (e.g. Robocop is a full-body cyborg of police officer Alex Murphy, in essence he is a human/robot police officer, which is the basic premise for the film). (Full article...) - Image 6Linimo (リニモ, Rinimo), formally the Aichi Rapid Transit Tobu Kyuryo Line (愛知高速交通東部丘陵線, Aichi Kōsoku Kōtsū Tōbu Kyūryō-sen) is a magnetic levitation train line in Aichi Prefecture, Japan, near the city of Nagoya. While primarily built to serve the Expo 2005 fair site, the line has since operated to serve the local community.
Linimo is owned and operated by the Aichi Rapid Transit Company, Ltd. (愛知高速交通株式会社, Aichi Kōsoku Kōtsū kabushiki gaisha) and is the first commercial maglev in Japan to use the High Speed Surface Transport (HSST) type technology. It is also the world's first uncrewed commercial urban maglev. Linimo was the fourth overall commercial urban maglev operated in the world, predated by the Birmingham Maglev (1984–1995), the Berlin M-Bahn (1989–1991) and the Shanghai Maglev (opened in 2004). (Full article...) - Image 7
Interstellar travel is the hypothetical travel of spacecraft from one star system, solitary star, or planetary system to another. Interstellar travel is expected to prove much more difficult than interplanetary spaceflight due to the vast difference in the scale of the involved distances. Whereas the distance between any two planets in the Solar System is less than 55 astronomical units (AU), stars are typically separated by hundreds of thousands of AU, causing these distances to typically be expressed instead in light-years. Because of the vastness of these distances, non-generational interstellar travel based on known physics would need to occur at a high percentage of the speed of light; even so, travel times would be long, at least decades and perhaps millennia or longer.
, five uncrewed spacecraft, all launched and operated by the United States, have achieved the escape velocity required to leave the Solar System as part of missions to explore parts of the outer system. They will therefore continue to travel through interstellar space indefinitely. However, they will not approach another star for hundreds of thousands of years, long after they have ceased to operate (though in theory the Voyager Golden Record would be playable in the event that the spacecraft is retrieved by an extraterrestrial civilization). (Full article...) - Image 8
A magnetorheological fluid (MR fluid, or MRF) is a type of smart fluid in a carrier fluid, usually a type of oil. When subjected to a magnetic field, the fluid greatly increases its apparent viscosity, to the point of becoming a viscoelastic solid. Importantly, the yield stress of the fluid when in its active ("on") state can be controlled very accurately by varying the magnetic field intensity. The upshot is that the fluid's ability to transmit force can be controlled with an electromagnet, which gives rise to its many possible control-based applications.
MR fluid is different from a ferrofluid which has smaller particles. MR fluid particles are primarily on the micrometre-scale and are too dense for Brownian motion to keep them suspended (in the lower density carrier fluid). Ferrofluid particles are primarily nanoparticles that are suspended by Brownian motion and generally will not settle under normal conditions. As a result, these two fluids have very different applications. (Full article...) - Image 9Virotherapy is a treatment using biotechnology to convert viruses into therapeutic agents by reprogramming viruses to treat diseases. There are three main branches of virotherapy: anti-cancer oncolytic viruses, viral vectors for gene therapy and viral immunotherapy. These branches use three different types of treatment methods: gene overexpression, gene knockout, and suicide gene delivery. Gene overexpression adds genetic sequences that compensate for low to zero levels of needed gene expression. Gene knockout uses RNA methods to silence or reduce expression of disease-causing genes. Suicide gene delivery introduces genetic sequences that induce an apoptotic response in cells, usually to kill cancerous growths. In a slightly different context, virotherapy can also refer more broadly to the use of viruses to treat certain medical conditions by killing pathogens. (Full article...)
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Earthquake-resistant or aseismic structures are designed to protect buildings to some or greater extent from earthquakes. While no structure can be entirely impervious to earthquake damage, the goal of earthquake engineering is to erect structures that fare better during seismic activity than their conventional counterparts. According to building codes, earthquake-resistant structures are intended to withstand the largest earthquake of a certain probability that is likely to occur at their location. This means the loss of life should be minimized by preventing collapse of the buildings for rare earthquakes while the loss of the functionality should be limited for more frequent ones.
To combat earthquake destruction, the only method available to ancient architects was to build their landmark structures to last, often by making them excessively stiff and strong. (Full article...) - Image 11
A coilgun is a type of mass driver consisting of one or more coils used as electromagnets in the configuration of a linear motor that accelerate a ferromagnetic or conducting projectile to high velocity. In almost all coilgun configurations, the coils and the gun barrel are arranged on a common axis. A coilgun is not a rifle as the barrel is smoothbore (not rifled).
Coilguns generally consist of one or more coils arranged along a barrel, so the path of the accelerating projectile lies along the central axis of the coils. The coils are switched on and off in a precisely timed sequence, causing the projectile to be accelerated quickly along the barrel via magnetic forces. (Full article...) - Image 12A multi-function material is a composite material. The traditional approach to the development of structures is to address the load-carrying function and other functional requirements separately. Recently, however, there has been increased interest in the development of load-bearing materials and structures which have integral non-load-bearing functions, guided by recent discoveries about how multifunctional biological systems work. (Full article...)
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Wearable technology is any technology that is designed to be used while worn. Common types of wearable technology include smartwatches and smartglasses. Wearable electronic devices are often close to or on the surface of the skin, where they detect, analyze, and transmit information such as vital signs, and/or ambient data and which allow in some cases immediate biofeedback to the wearer.
Wearable devices such as activity trackers are an example of the Internet of things, since "things" such as electronics, software, sensors, and connectivity are effectors that enable objects to exchange data (including data quality) through the internet with a manufacturer, operator, and/or other connected devices, without requiring human intervention. Wearable technology offers a wide range of possible uses, from communication and entertainment to improving health and fitness, however, there are worries about privacy and security because wearable devices have the ability to collect personal data. (Full article...) - Image 14
AeroVironment, Inc. is an American defense contractor headquartered in Arlington, Virginia, that designs and manufactures unmanned aerial vehicles (UAVs). Paul B. MacCready Jr., a designer of human-powered aircraft, founded the company in 1971. The company is best known for its lightweight human-powered and solar-powered vehicles. The company is the US military's top supplier of small drones —notably the Raven, Switchblade, Wasp and Puma models. (Full article...) - Image 15
Surveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing or directing. This can include observation from a distance by means of electronic equipment, such as closed-circuit television (CCTV), or interception of electronically transmitted information like Internet traffic. It can also include simple technical methods, such as human intelligence gathering and postal interception.
Surveillance is used by citizens, for instance for protecting their neighborhoods. It is widely used by governments for intelligence gathering, including espionage, prevention of crime, the protection of a process, person, group or object, or the investigation of crime. It is also used by criminal organizations to plan and commit crimes, and by businesses to gather intelligence on criminals, their competitors, suppliers or customers. Religious organizations charged with detecting heresy and heterodoxy may also carry out surveillance.
Auditors carry out a form of surveillance. (Full article...) - Image 16
A warship or combatant ship is a ship that is built and primarily intended for naval warfare. Usually they belong to the armed forces of a nation. As well as being armed, warships are designed to withstand damage and are typically faster and more maneuverable than merchant ships. Unlike a merchant ship, which carries cargo, a warship typically carries only weapons, ammunition and supplies for its crew. Warships usually belong to a navy, though they have also been operated by individuals, cooperatives and corporations.
In wartime, the distinction between warships and merchant ships is often blurred. Until the 17th century it was common for merchant ships to be pressed into naval service, and not unusual for more than half a fleet to be composed of merchant ships—there was not a large difference in construction, unlike the difference between a heavily armoured World War battleship and an ocean liner. Until the threat of piracy subsided in the 19th century, it was normal practice to arm larger merchant ships such as galleons. Warships have also often been used as troop carriers or supply ships, such as by the French Navy in the 18th century or the Imperial Japanese Navy during the Second World War. In war since the early 20th century, merchant ships were often armed and used as auxiliary warships, such as the Q-ships of the First World War and the armed merchant cruisers of the Second World War. (Full article...) - Image 17
An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without any human pilot, crew, or passengers on board. UAVs were originally developed through the twentieth century for military missions too "dull, dirty or dangerous" for humans, and by the twenty-first, they had become essential assets to most militaries. As control technologies improved and costs fell, their use expanded to many non-military applications. These include aerial photography, area coverage, precision agriculture, forest fire monitoring, river monitoring, environmental monitoring, policing and surveillance, infrastructure inspections, smuggling, product deliveries, entertainment, and drone racing. (Full article...) - Image 18
The Tweel (a portmanteau of tire and wheel) is an airless tire design developed by the French tire company Michelin. Its significant advantage over pneumatic tires is that the Tweel does not use a bladder full of compressed air, and therefore cannot burst, leak pressure, or become flat. Instead, the Tweel's hub is connected to the rim via flexible polyurethane spokes which fulfil the shock-absorbing role provided by the compressed air in a traditional tire. (Full article...) - Image 19
Armour (Commonwealth English) or armor (American English; see spelling differences) is a covering used to protect an object, individual, or vehicle from physical injury or damage, especially direct contact weapons or projectiles during combat, or from a potentially dangerous environment or activity (e.g. cycling, construction sites, etc.). Personal armour is used to protect soldiers and war animals. Vehicle armour is used on warships, armoured fighting vehicles, and some combat aircraft, mostly ground attack aircraft.
A second use of the term armour describes armoured forces, armoured weapons, and their role in combat. After the development of armoured warfare, tanks and mechanised infantry and their combat formations came to be referred to collectively as "armour". (Full article...) - Image 20
The AeroMobil s.r.o. AeroMobil is a prototype roadable aircraft, designed by Štefan Klein and first flown in 2013. The aircraft was going be produced by Slovak company AeroMobil s.r.o.
AeroMobil s.r.o. company co-founder and CEO Juraj Vaculík indicated in March 2015 that the vehicle is intended for "wealthy supercar buyers and flight enthusiasts". Aeromobil unveiled the production version of the vehicle in April 2017 and announced that it would be available for preorder before the end of 2017. (Full article...) - Image 21
Ammunition is the material fired, scattered, dropped, or detonated from any weapon or weapon system. Ammunition is both expendable weapons (e.g., bombs, missiles, grenades, land mines) and the component parts of other weapons that create the effect on a target (e.g., bullets and warheads).
The purpose of ammunition is to project a force against a selected target to have an effect (usually, but not always, lethal). An example of ammunition is the firearm cartridge, which includes all components required to deliver the weapon effect in a single package. Until the 20th century, black powder was the most common propellant used but has now been replaced in nearly all cases by modern compounds. (Full article...) - Image 22
DALL·E, DALL·E 2, and DALL·E 3 are text-to-image models developed by OpenAI using deep learning methodologies to generate digital images from natural language descriptions known as "prompts".
The first version of DALL-E was announced in January 2021. In the following year, its successor DALL-E 2 was released. DALL·E 3 was released natively into ChatGPT for ChatGPT Plus and ChatGPT Enterprise customers in October 2023, with availability via OpenAI's API and "Labs" platform provided in early November. Microsoft implemented the model in Bing's Image Creator tool and plans to implement it into their Designer app. (Full article...) - Image 23
A multi-agent system (MAS or "self-organized system") is a computerized system composed of multiple interacting intelligent agents. Multi-agent systems can solve problems that are difficult or impossible for an individual agent or a monolithic system to solve. Intelligence may include methodic, functional, procedural approaches, algorithmic search or reinforcement learning.
Despite considerable overlap, a multi-agent system is not always the same as an agent-based model (ABM). The goal of an ABM is to search for explanatory insight into the collective behavior of agents (which do not necessarily need to be "intelligent") obeying simple rules, typically in natural systems, rather than in solving specific practical or engineering problems. The terminology of ABM tends to be used more often in the science, and MAS in engineering and technology. Applications where multi-agent systems research may deliver an appropriate approach include online trading, disaster response, target surveillance and social structure modelling. (Full article...) - Image 24Software-defined radio (SDR) is a radio communication system where components that conventionally have been implemented in analog hardware (e.g. mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead implemented by means of software on a computer or embedded system. While the concept of SDR is not new, the rapidly evolving capabilities of digital electronics render practical many processes which were once only theoretically possible.
A basic SDR system may consist of a computer equipped with a sound card, or other analog-to-digital converter, preceded by some form of RF front end. Significant amounts of signal processing are handed over to the general-purpose processor, rather than being done in special-purpose hardware (electronic circuits). Such a design produces a radio which can receive and transmit widely different radio protocols (sometimes referred to as waveforms) based solely on the software used. (Full article...) - Image 25
Terraforming or terraformation ("Earth-shaping") is the hypothetical process of deliberately modifying the atmosphere, temperature, surface topography or ecology of a planet, moon, or other body to be similar to the environment of Earth to make it habitable for humans to live on.
The concept of terraforming developed from both science fiction and actual science. Carl Sagan, an astronomer, proposed the planetary engineering of Venus in 1961, which is considered one of the first accounts of the concept. The term was coined by Jack Williamson in a science-fiction short story ("Collision Orbit") published in 1942 in Astounding Science Fiction. (Full article...)
Selected global issues and related topics
- Image 1Overconsumption describes a situation where a consumer overuses their available goods and services to where they can't, or don't want to, replenish or reuse them. In microeconomics, this may be described as the point where the marginal cost of a consumer is greater than their marginal utility. The term overconsumption is quite controversial in use and does not necessarily have a single unifying definition. When used to refer to natural resources to the point where the environment is negatively affected, it is synonymous with the term overexploitation. However, when used in the broader economic sense, overconsumption can refer to all types of goods and services, including manmade ones, e.g. "the overconsumption of alcohol can lead to alcohol poisoning". Overconsumption is driven by several factors of the current global economy, including forces like consumerism, planned obsolescence, economic materialism, and other unsustainable business models and can be contrasted with sustainable consumption.
Defining the amount of a natural resource required to be consumed for it to count as "overconsumption" is challenging because defining a sustainable capacity of the system requires accounting for many variables. The total capacity of a system occurs at both the regional and worldwide levels, which means that certain regions may have higher consumption levels of certain resources than others due to greater resources without overconsuming a resource. A long-term pattern of overconsumption in any given region or ecological system can cause a reduction in natural resources that often results in environmental degradation. However, this is only when applying the word to human impacts on the environment. When used in an economic sense, this point is defined as when the marginal cost of a consumer is equal to their marginal utility. Gossen's law of diminishing utility states that at this point, the consumer realizes the cost of consuming/purchasing another item/good is not worth the amount of utility (also known as happiness or satisfaction from the good) they'd receive, and therefore is not conducive to the consumer's wellbeing.
When used in the environmental sense, the discussion of overconsumption often parallels that of population size and growth, and human development: more people demanding higher qualities of living, currently requires greater extraction of resources, which causes subsequent environmental degradation such as climate change and biodiversity loss. Currently, the inhabitants of high wealth, "developed" nations consume resources at a rate almost 32 times greater than those of the developing world, who make up the majority of the human population (7.9 billion people). However, the developing world is a growing consumer market. These nations are quickly gaining more purchasing power and it is expected that the Global South, which includes cities in Asia, America, and Africa, will account for 56% of consumption growth by 2030. This means that if current trends continue relative consumption rates will shift more into these developing countries, whereas developed countries would start to plateau. Sustainable Development Goal 12 "responsible consumption and production" is the main international policy tool with goals to abate the impact of overconsumption. (Full article...) - Image 2Gender equality, also known as sexual equality or equality of the sexes, is the state of equal ease of access to resources and opportunities regardless of gender, including economic participation and decision-making; and the state of valuing different behaviors, aspirations and needs equally, regardless of gender.
UNICEF defined gender equality as "women and men, and girls and boys, enjoy the same rights, resources, opportunities and protections. It does not require that girls and boys, or women and men, be the same, or that they be treated exactly alike."
gender equality is the fifth of seventeen sustainable development goals (SDG 5) of the United Nations; gender equality has not incorporated the proposition of genders besides women and men, or gender identities outside of the gender binary. Gender inequality is measured annually by the United Nations Development Programme's Human Development Reports. (Full article...) - Image 3Biotechnology risk is a form of existential risk from biological sources, such as genetically engineered biological agents. The release of such high-consequence pathogens could be
- deliberate (in the form of bioterrorism or biological weapons)
- accidental, or
- a naturally occurring event.
A chapter on biotechnology and biosecurity was included in Nick Bostrom's 2008 anthology Global Catastrophic Risks, which covered risks including viral agents. Since then, new technologies like CRISPR and gene drives have been introduced.
While the ability to deliberately engineer pathogens has been constrained to high-end labs run by top researchers, the technology to achieve this is rapidly becoming cheaper and more widespread. For example, the diminishing cost of sequencing the human genome (from $10 million to $1,000), the accumulation of large datasets of genetic information, the discovery of gene drives, and the discovery of CRISPR. Biotechnology risk is therefore a credible explanation for the Fermi paradox. (Full article...) - Image 4
Biodiversity loss happens when plant or animal species disappear completely from Earth (extinction) or when there is a decrease or disappearance of species in a specific area. Biodiversity loss means that there is a reduction in biological diversity in a given area. The decrease can be temporary or permanent. It is temporary if the damage that led to the loss is reversible in time, for example through ecological restoration. If this is not possible, then the decrease is permanent. The cause of most of the biodiversity loss is, generally speaking, human activities that push the planetary boundaries too far. These activities include habitat destruction and land use intensification (for example monoculture farming). Further problem areas are air and water pollution (including nutrient pollution), over-exploitation, invasive species and climate change.
Many scientists, along with the Global Assessment Report on Biodiversity and Ecosystem Services, say that the main reason for biodiversity loss is a growing human population because this leads to human overpopulation and excessive consumption. Others disagree, saying that loss of habitat is caused mainly by "the growth of commodities for export" and that population has very little to do with overall consumption. More important are wealth disparities between or within countries.
Climate change is another threat to global biodiversity. For example, coral reefs—which are biodiversity hotspots—will be lost by the year 2100 if global warming continues at the current rate. Still, it is the general habitat destruction (often for expansion of agriculture), not climate change, that is currently the bigger driver of biodiversity loss. Invasive species and other disturbances have become more common in forests in the last several decades. These tend to be directly or indirectly connected to climate change and can cause a deterioration of forest ecosystems. (Full article...) - Image 5
Health care, or healthcare, is the improvement of health via the prevention, diagnosis, treatment, amelioration or cure of disease, illness, injury, and other physical and mental impairments in people. Health care is delivered by health professionals and allied health fields. Medicine, dentistry, pharmacy, midwifery, nursing, optometry, audiology, psychology, occupational therapy, physical therapy, athletic training, and other health professions all constitute health care. The term includes work done in providing primary care, secondary care, and tertiary care, as well as in public health.
Access to healthcare may vary across countries, communities, and individuals, influenced by social and economic conditions as well as health policies. Providing health care services means "the timely use of personal health services to achieve the best possible health outcomes". Factors to consider in terms of healthcare access include financial limitations (such as insurance coverage), geographical and logistical barriers (such as additional transportation costs and the ability to take paid time off work to use such services), sociocultural expectations, and personal limitations (lack of ability to communicate with health care providers, poor health literacy, low income). Limitations to health care services affect negatively the use of medical services, the efficacy of treatments, and overall outcome (well-being, mortality rates).
Health systems are the organizations established to meet the health needs of targeted populations. According to the World Health Organization (WHO), a well-functioning healthcare system requires a financing mechanism, a well-trained and adequately paid workforce, reliable information on which to base decisions and policies, and well-maintained health facilities to deliver quality medicines and technologies. (Full article...) - Image 6Gray goo (also spelled as grey goo) is a hypothetical global catastrophic scenario involving molecular nanotechnology in which out-of-control self-replicating machines consume all biomass (and perhaps also everything else) on Earth while building many more of themselves, a scenario that has been called ecophagy (the literal consumption of the ecosystem). The original idea assumed machines were designed to have this capability, while popularizations have assumed that machines might somehow gain this capability by accident.
Self-replicating machines of the macroscopic variety were originally described by mathematician John von Neumann, and are sometimes referred to as von Neumann machines or clanking replicators.
The term gray goo was coined by nanotechnology pioneer K. Eric Drexler in his 1986 book Engines of Creation. In 2004, he stated "I wish I had never used the term 'gray goo'." Engines of Creation mentions "gray goo" as a thought experiment in two paragraphs and a note, while the popularized idea of gray goo was first publicized in a mass-circulation magazine, Omni, in November 1986. (Full article...) - Image 7
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is primarily caused by humans burning fossil fuels since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices add to greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary greenhouse gas driving global warming, has grown by about 50% and is at levels unseen for millions of years.
Climate change has an increasingly large impact on the environment. Deserts are expanding, while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has contributed to thawing permafrost, retreat of glaciers and sea ice decline. Higher temperatures are also causing more intense storms, droughts, and other weather extremes. Rapid environmental change in mountains, coral reefs, and the Arctic is forcing many species to relocate or become extinct. Even if efforts to minimise future warming are successful, some effects will continue for centuries. These include ocean heating, ocean acidification and sea level rise.
Climate change threatens people with increased flooding, extreme heat, increased food and water scarcity, more disease, and economic loss. Human migration and conflict can also be a result. The World Health Organization (WHO) calls climate change the greatest threat to global health in the 21st century. Societies and ecosystems will experience more severe risks without action to limit warming. Adapting to climate change through efforts like flood control measures or drought-resistant crops partially reduces climate change risks, although some limits to adaptation have already been reached. Poorer communities are responsible for a small share of global emissions, yet have the least ability to adapt and are most vulnerable to climate change. (Full article...) - Image 8
Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants.
Although environmental pollution can be caused by natural events, the word pollution generally implies that the contaminants have an anthropogenic source – that is, a source created by human activities, such as manufacturing, extractive industries, poor waste management, transportation or agriculture. Pollution is often classed as point source (coming from a highly concentrated specific site, such as a factory, mine, construction site), or nonpoint source pollution (coming from a widespread distributed sources, such as microplastics or agricultural runoff).
Many sources of pollution were unregulated parts of industrialization during the 19th and 20th centuries until the emergence of environmental regulation and pollution policy in the later half of the 20th century. Sites where historically polluting industries released persistent pollutants may have legacy pollution long after the source of the pollution is stopped. Major forms of pollution include air pollution, water pollution, litter, noise pollution, plastic pollution, soil contamination, radioactive contamination, thermal pollution, light pollution, and visual pollution. (Full article...) - Image 9
A pandemic (/pænˈdɛmɪk/ pan-DEM-ik) is an epidemic of an infectious disease that has spread across a large region, for instance multiple continents or worldwide, affecting a substantial number of individuals. Widespread endemic diseases with a stable number of infected individuals such as recurrences of seasonal influenza are generally excluded as they occur simultaneously in large regions of the globe rather than being spread worldwide.
Throughout human history, there have been a number of pandemics of diseases such as smallpox. The Black Death, caused by the Plague, caused the deaths of up to half of the population of Europe in the 14th century. The term pandemic had not been used then, but was used for later epidemics, including the 1918 H1N1 influenza A pandemic—more commonly known as the Spanish flu—which is the deadliest pandemic in history. The most recent pandemics include the HIV/AIDS pandemic, the 2009 swine flu pandemic and the COVID-19 pandemic. Almost all these diseases still circulate among humans though their impact now is often far less.
In response to the COVID-19 pandemic, 194 member states of the World Health Organization began negotiations on an International Treaty on Pandemic Prevention, Preparedness and Response, with a requirement to submit a draft of this treaty to the 77th World Health Assembly during its 2024 convention. Further, on 6 May 2024, the White House released an official policy to more safely manage medical research projects involving potentially hazardous pathogens, including viruses and bacteria, that may pose a risk of a pandemic. (Full article...) - Image 10
Societal collapse (also known as civilizational collapse or systems collapse) is the fall of a complex human society characterized by the loss of cultural identity and of social complexity as an adaptive system, the downfall of government, and the rise of violence. Possible causes of a societal collapse include natural catastrophe, war, pestilence, famine, economic collapse, population decline or overshoot, mass migration, incompetent leaders, and sabotage by rival civilizations. A collapsed society may revert to a more primitive state, be absorbed into a stronger society, or completely disappear.
Virtually all civilizations have suffered such a fate, regardless of their size or complexity, but some of them later revived and transformed, such as China, Greece, and Egypt. However, others never recovered, such as the Western and Eastern Roman Empires, the Maya civilization, and the Easter Island civilization.
Anthropologists, (quantitative) historians, and sociologists have proposed a variety of explanations for the collapse of civilizations involving causative factors such as environmental change, depletion of resources, unsustainable complexity, invasion, disease, decay of social cohesion, rising inequality, long-term decline of cognitive abilities, loss of creativity, and misfortune. However, complete extinction of a culture is not inevitable, and in some cases, the new societies that arise from the ashes of the old one are evidently its offspring, despite a dramatic reduction in sophistication. Moreover, the influence of a collapsed society, such as the Western Roman Empire, may linger on long after its death. (Full article...) - Image 11
Ozone depletion consists of two related events observed since the late 1970s: a steady lowering of about four percent in the total amount of ozone in Earth's atmosphere, and a much larger springtime decrease in stratospheric ozone (the ozone layer) around Earth's polar regions. The latter phenomenon is referred to as the ozone hole. There are also springtime polar tropospheric ozone depletion events in addition to these stratospheric events.
The main causes of ozone depletion and the ozone hole are manufactured chemicals, especially manufactured halocarbon refrigerants, solvents, propellants, and foam-blowing agents (chlorofluorocarbons (CFCs), HCFCs, halons), referred to as ozone-depleting substances (ODS). These compounds are transported into the stratosphere by turbulent mixing after being emitted from the surface, mixing much faster than the molecules can settle. Once in the stratosphere, they release atoms from the halogen group through photodissociation, which catalyze the breakdown of ozone (O3) into oxygen (O2). Both types of ozone depletion were observed to increase as emissions of halocarbons increased.
Ozone depletion and the ozone hole have generated worldwide concern over increased cancer risks and other negative effects. The ozone layer prevents harmful wavelengths of ultraviolet (UVB) light from passing through the Earth's atmosphere. These wavelengths cause skin cancer, sunburn, permanent blindness, and cataracts, which were projected to increase dramatically as a result of thinning ozone, as well as harming plants and animals. These concerns led to the adoption of the Montreal Protocol in 1987, which bans the production of CFCs, halons, and other ozone-depleting chemicals. Currently, scientists plan to develop new refrigerants to replace older ones. (Full article...) - Image 12
Biodiversity loss happens when plant or animal species disappear completely from Earth (extinction) or when there is a decrease or disappearance of species in a specific area. Biodiversity loss means that there is a reduction in biological diversity in a given area. The decrease can be temporary or permanent. It is temporary if the damage that led to the loss is reversible in time, for example through ecological restoration. If this is not possible, then the decrease is permanent. The cause of most of the biodiversity loss is, generally speaking, human activities that push the planetary boundaries too far. These activities include habitat destruction and land use intensification (for example monoculture farming). Further problem areas are air and water pollution (including nutrient pollution), over-exploitation, invasive species and climate change.
Many scientists, along with the Global Assessment Report on Biodiversity and Ecosystem Services, say that the main reason for biodiversity loss is a growing human population because this leads to human overpopulation and excessive consumption. Others disagree, saying that loss of habitat is caused mainly by "the growth of commodities for export" and that population has very little to do with overall consumption. More important are wealth disparities between or within countries.
Climate change is another threat to global biodiversity. For example, coral reefs—which are biodiversity hotspots—will be lost by the year 2100 if global warming continues at the current rate. Still, it is the general habitat destruction (often for expansion of agriculture), not climate change, that is currently the bigger driver of biodiversity loss. Invasive species and other disturbances have become more common in forests in the last several decades. These tend to be directly or indirectly connected to climate change and can cause a deterioration of forest ecosystems. (Full article...) - Image 13
Desertification is a type of gradual land degradation of fertile land into arid desert due to a combination of natural processes and human activities. This spread of arid areas is caused by a variety of factors, such as overexploitation of soil as a result of human activity and the effects of climate change. Geographic areas most affected are located in Africa (Sahel region), Asia (Gobi Desert and Mongolia) and parts of South America. Drylands occupy approximately 40–41% of Earth's land area and are home to more than 2 billion people. Effects of desertification include sand and dust storms, food insecurity, and poverty.
Humans can fight desertification in various ways. For instance, improving soil quality, greening deserts, managing grazing better, and planting trees (reforestation and afforestation) can all help reverse desertification.
Throughout geological history, the development of deserts has occurred naturally over long intervals of time. The modern study of desertification emerged from the study of the 1980s drought in the Sahel. (Full article...) - Image 14
A nuclear holocaust, also known as a nuclear apocalypse, nuclear annihilation, nuclear armageddon, or atomic holocaust, is a theoretical scenario where the mass detonation of nuclear weapons causes widespread destruction and radioactive fallout. Such a scenario envisages large parts of the Earth becoming uninhabitable due to the effects of nuclear warfare, potentially causing the collapse of civilization, the extinction of humanity, and/or the termination of most biological life on Earth.
Besides the immediate destruction of cities by nuclear blasts, the potential aftermath of a nuclear war could involve firestorms, a nuclear winter, widespread radiation sickness from fallout, and/or the temporary (if not permanent) loss of much modern technology due to electromagnetic pulses. Some scientists, such as Alan Robock, have speculated that a thermonuclear war could result in the end of modern civilization on Earth, in part due to a long-lasting nuclear winter. In one model, the average temperature of Earth following a full thermonuclear war falls for several years by 7 – 8 °C (13 to 15 degrees Fahrenheit) on average.
Early Cold War-era studies suggested that billions of humans would survive the immediate effects of nuclear blasts and radiation following a global thermonuclear war. The International Physicians for the Prevention of Nuclear War believe that nuclear war could indirectly contribute to human extinction via secondary effects, including environmental consequences, societal breakdown, and economic collapse. (Full article...) - Image 15
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is primarily caused by humans burning fossil fuels since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices add to greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary greenhouse gas driving global warming, has grown by about 50% and is at levels unseen for millions of years.
Climate change has an increasingly large impact on the environment. Deserts are expanding, while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has contributed to thawing permafrost, retreat of glaciers and sea ice decline. Higher temperatures are also causing more intense storms, droughts, and other weather extremes. Rapid environmental change in mountains, coral reefs, and the Arctic is forcing many species to relocate or become extinct. Even if efforts to minimise future warming are successful, some effects will continue for centuries. These include ocean heating, ocean acidification and sea level rise.
Climate change threatens people with increased flooding, extreme heat, increased food and water scarcity, more disease, and economic loss. Human migration and conflict can also be a result. The World Health Organization (WHO) calls climate change the greatest threat to global health in the 21st century. Societies and ecosystems will experience more severe risks without action to limit warming. Adapting to climate change through efforts like flood control measures or drought-resistant crops partially reduces climate change risks, although some limits to adaptation have already been reached. Poorer communities are responsible for a small share of global emissions, yet have the least ability to adapt and are most vulnerable to climate change. (Full article...) - Image 16Inclusive growth is economic growth that raises standards of livings for broad swaths of a population. Proponents for inclusive growth warn that inequitable growth may have adverse political outcomes.
The definition of inclusive growth implies direct links between the macroeconomic and microeconomic determinants of the economy and economic growth. The microeconomic dimension captures the importance of structural transformation for economic diversification and competition, while the macro dimension refers to changes in economic aggregates such as the country’s gross national product (GNP) or gross domestic product (GDP), total factor productivity, and aggregate factor inputs.
Sustainable economic growth requires inclusive growth. Maintaining this is sometimes difficult because economic growth may give rise to negative externalities, such as a rise in corruption, which is a major problem in developing countries. Nonetheless, an emphasis on inclusiveness—especially on equality of opportunity in terms of access to markets, resources, and an unbiased regulatory environment—is an essential ingredient of successful growth. The inclusive growth approach takes a longer-term perspective, as the focus is on productive employment as a means of increasing the incomes of poor and excluded groups and raising their standards of living. (Full article...) - Image 17
Food security is the state of having reliable access to a sufficient quantity of affordable, nutritious food. The availability of food for people of any class, gender or religion is another element of food security. Similarly, household food security is considered to exist when all the members of a family, at all times, have access to enough food for an active, healthy life. Individuals who are food-secure do not live in hunger or fear of starvation. Food security includes resilience to future disruptions of food supply. Such a disruption could occur due to various risk factors such as droughts and floods, shipping disruptions, fuel shortages, economic instability, and wars. Food insecurity is the opposite of food security: a state where there is only limited or uncertain availability of suitable food.
The concept of food security has evolved over time. The four pillars of food security include availability, access, utilization, and stability. In addition, there are two more dimensions that are important: agency and sustainability. These six dimensions of food security are reinforced in conceptual and legal understandings of the right to food. The World Food Summit in 1996 declared that "food should not be used as an instrument for political and economic pressure."
There are many possible causes of food insecurity. The most important ones are high food prices and disruptions in global food supplies for example due to war. There is also climate change, water scarcity, land degradation, agricultural diseases, pandemics and disease outbreaks that can all lead to food insecurity. (Full article...) - Image 18
Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. About 31% of Earth's land surface is covered by forests at present. This is one-third less than the forest cover before the expansion of agriculture, with half of that loss occurring in the last century. Between 15 million to 18 million hectares of forest, an area the size of Bangladesh, are destroyed every year. On average 2,400 trees are cut down each minute. Estimates vary widely as to the extent of deforestation in the tropics. In 2019, nearly a third of the overall tree cover loss, or 3.8 million hectares, occurred within humid tropical primary forests. These are areas of mature rainforest that are especially important for biodiversity and carbon storage.
The direct cause of most deforestation is agriculture by far. More than 80% of deforestation was attributed to agriculture in 2018. Forests are being converted to plantations for coffee, palm oil, rubber and various other popular products. Livestock grazing also drives deforestation. Further drivers are the wood industry (logging), urbanization and mining. The effects of climate change are another cause via the increased risk of wildfires (see deforestation and climate change).
Deforestation results in habitat destruction which in turn leads to biodiversity loss. Deforestation also leads to extinction of animals and plants, changes to the local climate, and displacement of indigenous people who live in forests. Deforested regions often also suffer from other environmental problems such as desertification and soil erosion. (Full article...) - Image 19Human overpopulation (or human population overshoot) describes a concern that human populations may become too large to be sustained by their environment or resources in the long term. The topic is usually discussed in the context of world population, though it may concern individual nations, regions, and cities.
Since 1804, the global human population has increased from 1 billion to 8 billion due to medical advancements and improved agricultural productivity. Annual world population growth peaked at 2.1% in 1968, and has since dropped to 1.1%. According to the most recent United Nations' projections, "[t]he global population is expected to reach 9.7 billion in 2050 and 10.4 billion in 2100." The UN's 2022 projections report predicted that the human population would peak at around 10.4 billion people in the 2080s, before decreasing, noting that fertility rates are falling worldwide. Other models agree that the population will stabilize before or after 2100. Conversely, other researchers have found that national birth registries data from 2022 and 2023 that cover half the world's population indicate that the 2022 UN projections overestimated fertility rates by 10 to 20% and are already outdated, that the global fertility rate has possibly already fallen below the sub-replacement fertility level for the first time in human history, and that the global population will peak at approximately 9.5 billion by 2061.
Early discussions of overpopulation in English were spurred by the work of Thomas Malthus. Discussions of overpopulation follow a similar line of inquiry as Malthusianism and its Malthusian catastrophe, a hypothetical event where population exceeds agricultural capacity, causing famine or war over resources, resulting in poverty and depopulation. More recent discussion of overpopulation was popularized by Paul Ehrlich in his 1968 book The Population Bomb and subsequent writings. Ehrlich described overpopulation as a function of overconsumption, arguing that overpopulation should be defined by a population being unable to sustain itself without depleting non-renewable resources. (Full article...) - Image 20
The 2007–2008 financial crisis, or the global financial crisis (GFC), was the most severe worldwide economic crisis since the Great Depression. Predatory lending in the form of subprime mortgages targeting low-income homebuyers, excessive risk-taking by global financial institutions, a continuous buildup of toxic assets within banks, and the bursting of the United States housing bubble culminated in a "perfect storm", which led to the Great Recession.
Mortgage-backed securities (MBS) tied to American real estate, as well as a vast web of derivatives linked to those MBS, collapsed in value. Financial institutions worldwide suffered severe damage, reaching a climax with the bankruptcy of Lehman Brothers on September 15, 2008, and a subsequent international banking crisis.
The preconditioning for the financial crisis was complex and multi-causal. Almost two decades prior, the U.S. Congress had passed legislation encouraging financing for affordable housing. However, in 1999, parts of the Glass-Steagall legislation, which had been adopted in 1933, were repealed, permitting financial institutions to commingle their commercial (risk-averse) and proprietary trading (risk-taking) operations. Arguably the largest contributor to the conditions necessary for financial collapse was the rapid development in predatory financial products which targeted low-income, low-information homebuyers who largely belonged to racial minorities. This market development went unattended by regulators and thus caught the U.S. government by surprise. (Full article...) - Image 21
Unemployment, according to the OECD (Organisation for Economic Co-operation and Development), is people above a specified age (usually 15) not being in paid employment or self-employment but currently available for work during the reference period.
Unemployment is measured by the unemployment rate, which is the number of people who are unemployed as a percentage of the labour force (the total number of people employed added to those unemployed).
Unemployment can have many sources, such as the following: (Full article...) - Image 22
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is primarily caused by humans burning fossil fuels since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices add to greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary greenhouse gas driving global warming, has grown by about 50% and is at levels unseen for millions of years.
Climate change has an increasingly large impact on the environment. Deserts are expanding, while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has contributed to thawing permafrost, retreat of glaciers and sea ice decline. Higher temperatures are also causing more intense storms, droughts, and other weather extremes. Rapid environmental change in mountains, coral reefs, and the Arctic is forcing many species to relocate or become extinct. Even if efforts to minimise future warming are successful, some effects will continue for centuries. These include ocean heating, ocean acidification and sea level rise.
Climate change threatens people with increased flooding, extreme heat, increased food and water scarcity, more disease, and economic loss. Human migration and conflict can also be a result. The World Health Organization (WHO) calls climate change the greatest threat to global health in the 21st century. Societies and ecosystems will experience more severe risks without action to limit warming. Adapting to climate change through efforts like flood control measures or drought-resistant crops partially reduces climate change risks, although some limits to adaptation have already been reached. Poorer communities are responsible for a small share of global emissions, yet have the least ability to adapt and are most vulnerable to climate change. (Full article...) - Image 23
Ocean acidification is the ongoing decrease in the pH of the Earth's ocean. Over the past 200 years, the rapid increase in anthropogenic CO2 (carbon dioxide) production has led to an increase in the acidity of the Earth’s oceans. Between 1950 and 2020, the average pH of the ocean surface fell from approximately 8.15 to 8.05. Carbon dioxide emissions from human activities are the primary cause of ocean acidification, with atmospheric carbon dioxide (CO2) levels exceeding 410 ppm (in 2020). CO2 from the atmosphere is absorbed by the oceans. This chemical reaction produces carbonic acid (H2CO3) which dissociates into a bicarbonate ion (HCO−3) and a hydrogen ion (H+). The presence of free hydrogen ions (H+) lowers the pH of the ocean, increasing acidity (this does not mean that seawater is acidic yet; it is still alkaline, with a pH higher than 8). Marine calcifying organisms, such as mollusks and corals, are especially vulnerable because they rely on calcium carbonate to build shells and skeletons.
A change in pH by 0.1 represents a 26% increase in hydrogen ion concentration in the world's oceans (the pH scale is logarithmic, so a change of one in pH units is equivalent to a tenfold change in hydrogen ion concentration). Sea-surface pH and carbonate saturation states vary depending on ocean depth and location. Colder and higher latitude waters are capable of absorbing more CO2. This can cause acidity to rise, lowering the pH and carbonate saturation levels in these areas. There are several other factors that influence the atmosphere-ocean CO2 exchange, and thus local ocean acidification. These include ocean currents and upwelling zones, proximity to large continental rivers, sea ice coverage, and atmospheric exchange with nitrogen and sulfur from fossil fuel burning and agriculture.
A lower ocean pH has a range of potentially harmful effects for marine organisms. Scientists have observed for example reduced calcification, lowered immune responses, and reduced energy for basic functions such as reproduction. Ocean acidification can impact marine ecosystems that provide food and livelihoods for many people. About one billion people are wholly or partially dependent on the fishing, tourism, and coastal management services provided by coral reefs. Ongoing acidification of the oceans may therefore threaten food chains linked with the oceans. (Full article...) - Image 24
Waste (or wastes) are unwanted or unusable materials. Waste is any substance discarded after primary use, or is worthless, defective and of no use. A by-product, by contrast is a joint product of relatively minor economic value. A waste product may become a by-product, joint product or resource through an invention that raises a waste product's value above zero.
Examples include municipal solid waste (household trash/refuse), hazardous waste, wastewater (such as sewage, which contains bodily wastes (feces and urine) and surface runoff), radioactive waste, and others. (Full article...) - Image 25
Water pollution (or aquatic pollution) is the contamination of water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and groundwater. Water pollution results when contaminants mix with these water bodies. Contaminants can come from one of four main sources. These are sewage discharges, industrial activities, agricultural activities, and urban runoff including stormwater. Water pollution may affect either surface water or groundwater. This form of pollution can lead to many problems. One is the degradation of aquatic ecosystems. Another is spreading water-borne diseases when people use polluted water for drinking or irrigation. Water pollution also reduces the ecosystem services such as drinking water provided by the water resource.
Sources of water pollution are either point sources or non-point sources. Point sources have one identifiable cause, such as a storm drain, a wastewater treatment plant or an oil spill. Non-point sources are more diffuse. An example is agricultural runoff. Pollution is the result of the cumulative effect over time. Pollution may take many forms. One would is toxic substances such as oil, metals, plastics, pesticides, persistent organic pollutants, and industrial waste products. Another is stressful conditions such as changes of pH, hypoxia or anoxia, increased temperatures, excessive turbidity, or changes of salinity). The introduction of pathogenic organisms is another. Contaminants may include organic and inorganic substances. A common cause of thermal pollution is the use of water as a coolant by power plants and industrial manufacturers.
Control of water pollution requires appropriate infrastructure and management plans as well as legislation. Technology solutions can include improving sanitation, sewage treatment, industrial wastewater treatment, agricultural wastewater treatment, erosion control, sediment control and control of urban runoff (including stormwater management). (Full article...)
Did you know...
- ... that the Backrooms is associated with an Internet aesthetic which includes images of eerie and uninhabited spaces?
- ... that Baer's pochard, found in eastern Asia, has seen a population decline of more than 99 percent in past decades, and is no longer migratory in central and eastern China?
- ... that al-Battani was one of the first astronomers to observe that the distance between the Earth and the Sun varies during the year?
- ... that Nicole Lloyd-Ronning returned to astrophysics research after a ten-year hiatus, aided by an American Physical Society award for women with interrupted careers?
- ... that the book A City on Mars covers sex in space, raising children in low gravity, space law, and space cannibalism?
- ... that a robotic controller for the Yamaha Reface CS was described by Mixmag magazine as looking "like an army of robot toothbrushes cleaning a synth"?
- ... that when astronaut Shannon Lucid returned to Earth after six months in orbit, she was presented with a box of M&M's?
- ... that despite having been enlarged for the 1939 New York World's Fair, the Willets Point Boulevard station served practically no resident population by 1949?
- ... that Eileen Collins was the first woman Space Shuttle pilot and the first woman to command a Space Shuttle mission?
- ... that Malinau Kota, Indonesia, with 31 percent of the population of Malinau Regency, is home to more than 70 percent of its registered restaurants?
- ... that Jim Hobbins played two years of professional football, spaced apart by 11 years?
- ... that Lillian V. Holdeman Moore identified a spike in hydrogen-gas-producing bacteria in Skylab astronauts?
- ... that in the 1909 election to the city council of Surabaya, less than 1 percent of the population was enrolled to vote?
- ... that Jay Owen Light aspired to be an astronaut before becoming the dean of Harvard Business School?
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Selected images that captured my attention
- Image 1A dust storm rushes towards a military camp as it rolls over Al Asad Airbase, Iraq, just before nightfall on April 27, 2005. A dust storm (or sandstorm) is a meteorological phenomenon common in dry, arid and semi-arid regions, usually the result of convection currents created by intense heating of the ground. These currents then carry clouds of sand over large distances.
- Image 2Astronaut Buzz Aldrin saluting the flag of the United States, part of the Lunar Flag Assembly, during Apollo 11. The Lunar Flag Assembly was designed to survive a Moon landing and to appear to "wave" as it would in a breeze on Earth. This flag fell over when the Lunar Module Eagle took off.
- Image 3Burj Khalifa is a skyscraper in Dubai, United Arab Emirates, and currently the tallest man-made structure in the world, at 829.8 m (2,722 ft). It was designed to be the centerpiece of a large-scale, mixed-use development known as Downtown Dubai. Construction took over five years, and the skyscraper was officially opened in January 2010.
- Image 4One of two monkey selfies taken by Celebes crested macaques using equipment belonging to the British nature photographer David Slater. In mid-2014, the images' hosting on Wikimedia Commons was at the centre of a dispute over whether copyright could be held on artworks made by non-human animals. Slater argued that, as he had "engineered" the shot, he held copyright, while Wikimedia considered the photographs public domain on the grounds that they were made by an animal rather than a person. In December 2014, the United States Copyright Office stated that works by a non-human are not subject to US copyright, a view reaffirmed by a US federal judge in 2016.
- Image 5Sandboarding is a boardsport similar to snowboarding, but competitions take place on sand dunes rather than snow-covered mountains. Here, a member of the US Navy sandboards down a dune in Jebel Ali, Dubai.
- Image 6A neutral density filter is a filter that reduces or modifies the intensity of all wavelengths or colors of light equally, giving no changes in hue of color rendition. The filter reduces the amount of light entering the lens, allowing the photographer to select combinations of aperture, exposure time and sensor sensitivity to avoid overexposed pictures. It would normally be attached to the lens, but is hand-held here to illustrate the effect.
- Image 7Tracy Caldwell Dyson in the Cupola module of the International Space Station, observing the Earth below during Expedition 24. Caldwell Dyson is an American chemist and astronaut. She was selected by NASA in 1998 and made her first spaceflight in August 2007 on the STS-118 mission aboard Space Shuttle Endeavour.
- Image 8Crash landing of an F6F Hellcat into the port side 20mm gun gallery of the USS Enterprise, November 10, 1943. Lieutenant Walter L. Chewning, Jr., USNR, the Catapult Officer, is climbing up the plane's side to assist the pilot from the burning aircraft. The pilot, Ensign Byron M. Johnson, escaped without significant injury. Note the plane's ruptured belly fuel tank.
- Image 9Imagine waking up to this. Which makes me wonder whatever happened to the guy who took this photo.
- Image 10The I-35W Mississippi River bridge was an eight-lane, steel truss arch bridge that carried Interstate 35W across the Saint Anthony Falls of the Mississippi River in Minneapolis, Minnesota. Once the third-busiest bridge in the state, it suddenly collapsed on August 1, 2007, killing 13 and injuring 145. Rescue of people stranded on the bridge was complete in three hours, while recovery of bodies—involving 75 local, state and federal agencies—took three weeks. An NTSB investigation cited a design flaw as the likely cause of the collapse, noting that a too-thin gusset plate ripped along a line of rivets.
- Image 11A swan created using modular origami, a paperfolding technique which uses two or more sheets of paper to create a larger and more complex structure than possible with single-piece origami techniques. Each individual sheet of paper is folded into a module, or unit, and then modules are assembled into an integrated flat shape or three-dimensional structure by inserting flaps into pockets created by the folding process. These insertions create tension or friction that holds the model together.
- Image 12Glaucus atlanticus is a species of small, blue sea slug. This pelagic aeolid nudibranch floats upside down, using the surface tension of the water to stay up, and is carried along by the winds and ocean currents. The blue side of their body faces upwards, blending in with the blue of the water, while the grey side faces downwards, blending in with the silvery surface of the sea. G. atlanticus feeds on other pelagic creatures, including the Portuguese man o' war.
- Image 13San Francisco Bay shrouded in fog, as seen from the Marin Headlands looking east. The fog of San Francisco is a kind of sea fog, created when warm, moist air blows from the central Pacific Ocean across the cold water of the California Current, which flows just off the coast. The water is cold enough to lower the temperature of the air to the dew point, causing fog generation. In this photo, the towers of the Golden Gate Bridge can be seen poking through the fog, and the Bay Bridge is visible in the distance.
- Image 14View from Notre-Dame de Paris.
- Image 15The Leaning Tower of Pisa is the freestanding bell tower of the Cathedral of Pisa, Italy. The third oldest structure in the city's Square of Miracles, it is known worldwide for its unintended tilt. The tower's tilt began during construction in the 12th century, caused by an inadequate foundation on ground too soft on one side to properly support the structure's weight. The tilt gradually increased until the tower was stabilized (and the tilt partially corrected) by efforts in the late 20th and early 21st centuries. The tower, which measures 55.86 metres (183.27 feet) from the ground on the low side and 56.67 metres (185.93 feet) on the high side, has been listed as a UNESCO World Heritage Site since 1987.
- Image 16The Thinker
- Image 17Crowds surrounding the Reflecting Pool, during the August 28 1963 March on Washington for Jobs and Freedom. An estimated 200,000 to 500,000 people participated in the march, which featured Martin Luther King Jr.'s famous "I Have a Dream" speech. It was a major factor leading to the passage of the Civil Rights Act of 1964 and the 1965 Voting Rights Act. The march was also condemned by the Nation of Islam and Malcolm X, who termed it the "farce on Washington".
- Image 18You are feeling very sleepy...
- Image 19The International Space Station (ISS) as seen from the Space Shuttle Endeavour. Zarya, the first module of the ISS launched in 1998, is seen in the foreground. Since then, twenty-six Space Shuttle flights have docked with the ISS to assemble various other modules and components, which include four pairs of solar arrays seen on each side.
- Image 20NGC 1300 is a barred spiral galaxy located roughly 69 million light-years away in the direction of the constellation Eridanus. In its core, the nucleus shows its own extraordinary and distinct "grand-design" spiral structure that is about 3,300 light-years long.
- Image 21American astronaut Eugene Cernan (born March 14, 1934), shown here on the surface of the Moon during the Apollo 17 mission, the last time any human has set foot on it. In that final lunar landing mission, launched December 7, 1972, Cernan became "the last man on the moon" since he was the last to re-enter the Apollo Lunar Module during its third and final extra-vehicular activity. Prior to this, Cernan had also gone into space twice on the Gemini 9A and Apollo 10 missions.
- Image 22The Door to Hell is a natural gas field in Derweze, Turkmenistan, which has been burning since 1971 when it was ignited by Soviet scientists who expected it to burn out within days. They were trying to prevent the release of poisonous gases. The name "Door to Hell" was given to the field by locals. The hot spots range over an area with a width of 60 metres (200 ft) and to a depth of about 20 metres (66 ft).
- Image 23The American Bison, or Buffalo, is the largest terrestrial mammal in North America, and once inhabited the Great Plains in massive herds. They were central to the lives of Native American tribes. This pile of bison skulls from the 1870s illustrates the extent of their slaughter in the 19th century by settlers: from a population of about 60 million in 1800 to as few as 750 in 1890. They have since been reintroduced into the wild and are no longer considered a high risk endangered species.
- Image 24The 2004 Indian Ocean earthquake was a magnitude 9.15, undersea earthquake that occurred at 00:58:53 UTC on December 26 2004. The earthquake generated a tsunami that killed more than 150,000 people around the Indian Ocean, making it one of the deadliest disasters in modern history. This photograph shows the tsunami as it reached Ao Nang, Thailand.
- Image 25The Aqueduct of Segovia is a Roman aqueduct located in Segovia, Spain that transports water from the Rio Frio. It is thought to have been constructed during the 1st century CE. One of the most significant and best-preserved ancient monuments left on the Iberian Peninsula, the aqueduct is considered a symbol of Segovia and is present on the city's coat of arms.
- Image 26
- Image 27aurora australis, as seen from the International Space Station. Aurorae are natural light displays in the sky caused by the collision of energetic charged particles with atoms in the high altitude thermosphere. The particles originate in the magnetosphere and solar wind and, on Earth, are directed by Earth's magnetic field into the atmosphere.
- Image 28United States Navy personnel engage in Special Patrol Insertion/Extraction (SPIE) training between a Sikorsky SH-60 Seahawk helicopter and the USS Dwight D. Eisenhower (CVN-69). SPIE involves either a person or goods being lowered from or raised to a helicopter via a cable above terrain on which landing would be difficult.
- Image 29A man engaging in big wave surfing at Mavericks, located just north of Half Moon Bay, California. Big wave surfing is a discipline within surfing in which experienced surfers paddle into or are towed onto waves which are at least 20 ft (6.1 m) high, and is a hazardous activity, as surfers can be pushed far beneath the surface of the water after a wipeout.
- Image 30Devastation caused by Hurricane Katrina in New Orleans, Louisiana during 2005, shown here looking down on Interstate 10 at West End Boulevard towards Lake Pontchartrain. Over 1,800 people were confirmed dead with 705 still missing. It was the costliest Atlantic hurricane in history causing around $86 billion in damage. This photo shows flooded roadways as the United States Coast Guard conducted initial damage assessment overflights of New Orleans on Monday, August 29, 2005. The city flooded due primarily to the failure of the levee system. Many who remained in their homes had to swim for their lives, wade through deep water, or remain trapped in their attics or on their rooftops.
- Image 31Atlantic White-sided Dolphins, on a concrete-floored dock at the port of Hvalba, which is in the Faroe Islands, north of the United Kingdom. Whaling in the Faroe Islands has been practised since at least the 10th century. It is strongly regulated by Faroese authorities and is approved by the International Whaling Commission.
- Image 32A lava lake at Mount Nyiragongo, a volcano found in Virunga National Park in the Democratic Republic of the Congo. Lava lakes, which can form in three different ways, are large volumes of molten lava, usually basaltic, contained in a volcanic vent, crater, or broad depression. Persistent lava lakes such as the one at Nyiragongo, which is the largest to appear in recent times, are rare.
- Image 33A Marginated Tortoise hatchling.
- Image 34The "Baker" explosion, part of Operation Crossroads, a nuclear weapon test by the United States military at Bikini Atoll, Micronesia, on July 25, 1946. Its purpose was to test the effect of nuclear weapons on naval ships. It was the second US nuclear bomb set off since the bombing of Nagasaki.
- Image 35The Pinwheel Galaxy is a face-on spiral galaxy located 21 million light-years away in the constellation Ursa Major. It was first discovered by Pierre Méchain on March 27, 1781, and communicated to Charles Messier, who verified its position for inclusion in the Messier Catalogue as one of its final entries. This image, released on February 28, 2006, is composed of 51 individual exposures, as well as some extra ground-based photos. At the time of its release, it was the largest and most detailed image of a galaxy by the Hubble Space Telescope.
- Image 36An overhead view of Skylab, the United States' first space station, in Earth orbit as photographed from the Skylab 4 Command and Service Modules. Skylab 4 was the last mission to Skylab and brought back its final crew; this photograph was the last one taken of the station before the mission re-entered Earth's atmosphere and disintegrated in 1979.
- Image 37Lucky Diamond Rich (b. 1971) is a New Zealand-born performance artist and street performer who holds the Guinness World Record for most tattooed man, taking the title from Tom Leppard in 2006. He is recognized by Guinness as being covered in tattoos over 100% of his body, including the inside of his eyelids, ears, and mouth.
- Image 38
- Image 39The mushroom cloud from the Ivy Mike nuclear test, one of two tests conducted as part of Operation Ivy at the Pacific Proving Grounds on Elugelab in the Marshall Islands. Mike was the first successful full-scale test of a multi-megaton thermonuclear weapon, and it left an underwater crater 6,240 ft (1,900 m) wide and 164 ft (50 m) deep where the island had been.
- Image 40The mushroom cloud caused by the detonation of the "Fat Man" bomb during the atomic bombing of Nagasaki, Japan in 1945, rising approximately 18 kilometres (11 mi) above the hypocenter.
- Image 41The Hubble Extreme Deep Field is an image of a small area of space in the constellation Fornax released by NASA on September 25, 2012. The successor to the Hubble Ultra-Deep Field, this image was compiled from 10 years of previous images with a total exposure time of two million seconds, or approximately 23 days.
- Image 42An animation of a cicada undergoing ecdysis, the molting of the exoskeleton in arthropods and related groups. Since the cuticula of these animals is inelastic, it is shed during growth and a new, larger covering is formed. The old, empty exoskeleton is called an exuvia. Within one or two hours, the cuticle hardens and darkens, during which time the animal grows, since growth is otherwise constrained by the rigidity of the exoskeleton. Each frame of this image was taken at one-minute intervals, with a 30-minute gap in middle while the cicada rested. The entire process took about 2 hours to complete.
- Image 43The sperm whale is the largest toothed animal on Earth. The species was hunted extensively by humans throughout history, until protected by a worldwide moratorium on whaling starting in 1985–86.
- Image 44Height comparison of notable statues: 1) Statue of Unity 240 m. 2) Spring Temple Buddha 153 m. 3) Statue of Liberty 93 m. 4) The Motherland Calls 91 m. 5) Christ the Redeemer 39.6 m. 6) Statue of David 5.17 m.
- Image 45Sand castle
Trump news tracker
- 30 May 2024 – Prosecution of Donald Trump in New York
- Former President of the United States Donald Trump is found guilty by a jury on all 34 felony counts relating to falsifying business records, becoming the first U.S. president to be convicted of a crime. (CNN)
- 15 May 2024 – 2024 United States presidential election
- U.S. President Joe Biden and presumptive Republican nominee Donald Trump agree to hold a presidential debate on June 27, hosted by CNN, which will be the earliest general election debate in modern history in the United States. A second debate will be held in September. (The New York Times)
- 30 April 2024 – Prosecution of Donald Trump in New York
- Judge Juan Merchan fines Donald Trump $9,000 for contempt of court, and threatens to jail Trump if he continues to violate his gag order. (Reuters)
- 19 April 2024 – Self-immolation of Maxwell Azzarello
- A man fatally sets himself on fire near the New York City courthouse where former President Donald Trump is currently on trial. (The New York Times)
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