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    Science

    How can the sky be blue one day and stormy the next? Why do heavy objects tend to fall downwards when dropped? How are birds able to fly (and why can’t I do the same?)? Human beings have long been curious about the world in which we live, striving to identify connections among the phenomenons we witness and to understand how it all works. The field of science has developed over many centuries as a way of studying and understanding the world, beginning with the primitive stage of simply noting important regularities in nature and continuing through the rise of modern science. The modern-day sciences cover a vast range of fields, including biology, chemistry, meteorology, astronomy, physics, and much more.
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    Featured content, September 18, 2020

    10 Deadly Animals that Fit in a Breadbox
    Tiny terrors of the animal kingdom.
    #WTFact / Science
    Mosquito on human skin.
    What Is Known (and Not Known) About Contrails
    A condensation trail, or “contrail,” is a streamer of cloud sometimes observed behind an airplane. Learn more about where...
    Companion / Science
    Airplane in the sky with a trace of steam contrail.
    What’s the Difference Between Llamas and Alpacas?
    While often conflated, alpacas and llamas differ in key ways.
    Demystified / Science
    Alpaca and Llama side by side
    7 of the World’s Deadliest Plants
    Think plants aren’t scary? Think again.
    List / Science
    Close-up of tobacco plants in Ontario, Canada. Tobacco, Nicotiana, cured leaves used after processing in various ways for smoking, snuffing, chewing, and extracting of nicotine.
    Analysis
    Analysis, a branch of mathematics that deals with continuous change and with certain general types of processes that have...
    Encyclopedia / Science
    The transformation of a circular region into an approximately rectangular regionThis suggests that the same constant (π) appears in the formula for the circumference, 2πr, and in the formula for the area, πr2. As the number of pieces increases (from left to right), the “rectangle” converges on a πr by r rectangle with area πr2—the same area as that of the circle. This method of approximating a (complex) region by dividing it into simpler regions dates from antiquity and reappears in the calculus.
    STEM
    STEM, field and curriculum centred on education in the disciplines of science, technology, engineering, and mathematics (STEM)....
    Encyclopedia / Science
    Copley Medal
    Copley Medal, the most prestigious scientific award in the United Kingdom, given annually by the Royal Society of London...
    Encyclopedia / Science
    The Royal Society's Copley Medal (obverse), bearing the likeness of the award's bequeather, Sir Godfrey Copley, 2nd Baronet (c. 1653–1709).
    Mathematics
    Mathematics, the science of structure, order, and relation that has evolved from elemental practices of counting, measuring,...
    Encyclopedia / Science
    Babylonian mathematical tablet.

    Science Quizzes

    Dog playing and chasing ball. (pet; canine; domestic animal)
    Dogs Quiz
    Test your knowledge about dogs with this quiz.
    Cougar in woods. Cats, felines, puma.
    The Big Cats
    Although photographs and videos of cute domesticated cats are frequent subjects of Internet searches and social media posts,...
    Periodic table of the elements. Chemistry matter atom
    Chemistry: Fact or Fiction?
    Test your knowledge of the fascinating science of chemistry.
    Collage of different cats. Made for the cat quiz on Mendel
    Cat Quiz
    How much do you know about cats?
    Pangaea (Pangea) was a supercontinent 225 million years ago formed by plate tectonics and continental drift.
    Name That Geologic Interval
    How much do you really know about Earth’s geologic history?
    Cave pool thermal spring in Grjotagja Cave, near Myvatn lake in Iceland. Groundwater. Lava cave
    Groundwater Quiz
    You may know all about what happens to water aboveground, but what do you know about groundwater? Test your knowledge with...
    Ultraviolet image of Venus' clouds as seen by the Pioneer Venus orbiter; February 26, 1979.
    Venus
    How much do you know about the second planet from the Sun? Test your knowledge with this quiz.
    Great Grey Owl or Great Gray Owl (Strix nebulosa), Alaska. Wood owls, birds.
    Owl Quiz
    How much do you know about owls?
    Almond, Food, Nut, food, Snack, Raw Food
    Nut or Not?
    Do you know which culinary nuts are true botanical nuts?
    Specially designed Cassini orbits place Earth and Cassini on opposite sides of Saturn's rings, a geometry known as occultation. Cassini conducted the first radio occultation observation of Saturn's rings on May 3, 2005. (solar system, planets)
    Saturn
    What’s in Saturn’s atmosphere? Who discovered Saturn’s rings? What are the seasons like? Test your knowledge about these...
    Image Gallery
    Science
    Never Miss a Day in History
    Sign up for daily fun facts about this day in history, updates, and special offers delivered right to your inbox.

    Science Subcategories

    subcategory placeholder Astronomy
    Human beings have always been fascinated by the celestial sphere above, whose twinkling lights have inspired many theories and artistic endeavors. Study of the solar system has provoked more than just peaceful meditation, however; a major controversy among astronomers arose in the 16th century when Copernicus publicly championed heliocentrism, a Sun-centric model of the solar system that was in direct opposition to Ptolemy's Earth-centered model, which had been generally accepted from the 2nd century CE onward. But humankind's fascination with the world beyond Earth has also led to some landmark moments in history, as when space exploration took a giant step forward with the advent of technology that allowed humans to travel to the Moon and to build spacecraft capable of exploring the rest of the solar system and beyond.
    Articles
    Chordate Biology
    If it’s alive, biology will define it, study it, observe all its functions, follow its vital processes, and interact with it, all in order to understand the life that animates it. In one of biology's best-known examples of such studious investigation, Charles Darwin came up with his scientific theory of evolution by natural selection after systematically observing a variety of plants and animals; his work acted as the foundation upon which modern evolutionary theory is built. But biology’s principles also operate within a plethora of other related fields, including biochemistry, biomedicine, biophysics, and microbiology.
    Articles
    Black girdle-tailed lizard (Cordylus nigra). Birds, Reptiles & Other Vertebrates
    Although it can be hard to imagine that a peacock and a crocodile have much of anything in common, these animals are actually descendants of the same prehistoric vertebrates. Birds are thought to have descended from carnivorous dinosaurs that began growing feathers by the Late Jurassic Period; thus, birds are technically one lineage of reptiles. This evolutionary link highlights the way in which seemingly incongruous creatures can, in fact, share a common ancestor (though that doesn't mean that we should expect waterfowl and crocodiles to become friends anytime soon).
    Articles
    Mantid (Mantis religiosa). Bugs, Mollusks & Other Invertebrates
    Some insects are so displeasing to humans that the word "bug" has come to be used as a verb meaning "to bother or annoy." Yet, in addition to being critically important—because they naturally recycle decaying matter—in maintaining balance within the food chain, bugs can also be fascinating creatures, whether in regard to the water strider's ability to run across the surface of water or in regard to assassin bugs' varied and creative means of catching and killing their prey. Mollusks, another group of invertebrates, get less of a bad rap. Their ranks include nearly 100,000 described species of soft-bodied animals that are usually wholly or partly enclosed in a calcium carbonate shell; examples include snails, clams, oysters, squids, and octopuses.
    Articles
    periodic table Chemistry
    How do you use raw plant materials to manufacture a best-selling perfume? How do you engineer household products that are compliant with environmentally-oriented guidelines? The answers to these questions require an understanding of the laws of chemistry, the science that deals with the properties, composition, and structure of elements and compounds, as well as the transformations that such substances undergo and the energy that is released or absorbed during those processes. Chemistry is also concerned with the utilization of natural substances and the creation of artificial ones. Over time, more than 8,000,000 different chemical substances, both natural and artificial, have been characterized and produced. Chemistry's vast scope comprises organic, inorganic, physical, analytical, and industrial chemistry, along with biochemistry, environmental chemistry, medicinal chemistry, and much more. Through the dedicated efforts of people such as Robert Boyle, Dmitri Mendeleev, John Dalton, Marie Curie, and Rosalind Franklin, the field of chemistry has led to exciting innovations as well as crucial advances in our understanding of how the world functions, starting with just the miniscule and unassuming atom.
    Articles
    subcategory placeholder Earth Science, Geologic Time & Fossils
    Planet Earth has billions of years of history, from the time when it was an inhospitable ball of hot magma to when its surface stabilized into a variety of beautiful and diverse zones capable of supporting many life-forms. Many are the species that lived through the various geologic eras and left a trace of their existence in the fossils that we study today. But Earth is never done settling, as we can see from the earthquakes, tsunamis, volcanic eruptions, and other phenomena manifested in Earth’s crust, oceans, and atmosphere.
    Articles
    Grinnell Glacier shrinkage Environment
    Biological diversity is key to a healthy ecosystem, whether it’s a small biological community or the global biosphere. Ecology, which studies the relationships between organisms and their environment, is an invaluable science that helps us understand what allows an ecological community to thrive.
    Articles
    Meerkat, or suricate (Suricata suricatta). Mammals
    These are the animals to which humans tend to relate the most, perhaps because aspects of their behavior can sometimes resemble the way that we ourselves behave. The protective instinct of a mother bear, the gamboling way that kittens play, and the loyalty displayed by a dog are all traits that we can identify with in the course of our own lives. Mammals are well-equipped to handle different climates and biomes because of their ability to regulate their own body temperatures and internal environment, both in excessive heat and aridity and in severe cold.
    Articles
    Plot of the cubic equation f(x) = x3 ? 3x + 2. The plotted points are where changes in curvature occur. Mathematics
    Although stock portrayals of mathematicians often involve a studious person standing in front of a chalkboard that's covered with mind-bogglingly complex scrawled mathematical problems (call it the "Good Will Hunting" effect), the chaotic-looking equations may obscure the fact that mathematics is, at its heart, a science of structure, order, and relation that deals with logical reasoning and quantitative calculation. There's a method to all that madness! The history of mathematics can be traced back to ancient Mesopotamia, whose clay tablets revealed that the level of mathematical competence was already high as early as roughly the 18th century BCE. Over the centuries, mathematics has evolved from elemental practices of counting, measuring, and describing the shapes of objects into a crucial adjunct to the physical sciences and technology.
    Articles
    mandacaru cactus Plants
    Life on Earth owes much to plants. The vast majority of plants carry out photosynthesis to transform light energy into chemical energy, which is the way that virtually all energy in the biosphere becomes available to living things (including us humans). As photosynthetic organisms, plants occupy the base of Earth's food webs and are consumed directly or indirectly by all higher life-forms, thereby functioning as the major source of food for humans and other animals. Plants' photosynthetic activity also produces the air that we breathe: almost all the oxygen in the atmosphere is due to the process of photosynthesis. Still not convinced about the merits of plants? Consider the fact that many plants not only serve up crucial nutrients and breathable air but also look good doing it. Many plants are admired for their striking aesthetic qualities, and flowers such as tulips, lilies, sunflowers, and daisies beautify fields, gardens, windowsills, and bouquets the world over. Plants are also a primary source of consumer goods, such as building materials, textile fibers, and pharmaceuticals.
    Articles
    Acoustics Physics
    What’s the matter? The matter is our whole observable universe—with that material substance that constitutes it—and it is the subject of study of physics. The laws that govern motion observed by Newton, the gravitational force that regulates the progress of all celestial bodies, the interaction between subatomic particles, and the nuclear engineering that created the atomic bomb are examples of what this important discipline is all about. Minkowski’s space-time concept, which reformulated Einstein’s special theory of relativity, has bridged physics with philosophy in a conversation that has fascinated the modern concept of physics.
    Articles
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