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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, March 11, 2021

What’s the Difference Between a Glacier and an Ice Floe?
They’re both huge masses of ice, right?
Demystified / Science
Glacier off coast of  Argentina, South America. (glacial; snow; ice; blue ice; melting glacier)
The Real Science Behind Frankenstein
How Mary Shelley’s imagination came alive
#WTFact / Science
Frankenstein, Boris Karloff (1931). Directed by James Whale
Why Is the Platypus a Mammal?
The platypus has a bill and webbed feet like a duck and venom like a snake. And it lays eggs. Despite all of this, it’s classed...
Companion / Science
Platypus (Ornithorhynchus anatinus) swimming on the surface of a creek. Water Australia mammal monotreme
10 Places to Visit in the Solar System
Having a tough time deciding where to go on vacation? The solar system is full of amazing (and uncrowded) destinations.
List / Science
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)
Heredity
Heredity, the sum of all biological processes by which particular characteristics are transmitted from parents to their offspring....
Encyclopedia / Science
human chromosomes
Meta-analysis
Meta-analysis, in statistics, approach to synthesizing the results of separate but related studies. In general, meta-analysis...
Encyclopedia / Science
Astronomy
Astronomy, science that encompasses the study of all extraterrestrial objects and phenomena. Until the invention of the telescope...
Encyclopedia / Science
Hubble Space Telescope
Scientific Revolution
Scientific Revolution, drastic change in scientific thought that took place during the 16th and 17th centuries. A new view...
Encyclopedia / Science
Copernican system

Science Quizzes

Stratosphere. cloud. View of horizon from airplane of Cumulus clouds. Cirrus, Stratus, weather
Clouds: Fact or Fiction?
Are clouds made up of water? Are the highest clouds called stratus? Sort fact from fiction in this quiz about clouds.
A composite of six separate orbits taken on January 23, 2012 by the Suomi National Polar-orbiting Partnership satellite. It was taken by a new instrument flying aboard Suomi NPP, the Visible Infrared Imaging Radiometer Suite (VIIRS) Blue Marble 2012 Earth
Planet Earth: Fact or Fiction?
Are all icebergs found near the Earth’s poles? Is hydrogen common everywhere on Earth? Test your knowledge of planet Earth...
earth. Cross section illustration of the layers of Planet Earth with liquid layer of outer core, crust, mantle and inner core.
Characteristics of Earth: Fact or Fiction?
Is it true that life can only evolve on Earth? From our planet’s equator to its inner core, let your knowledge of Earth evolve...
Microscope (medical, science, research, magnify, object, outlined, biology).
Microscopes and Telescopes: Fact or Fiction?
Is the Hubble Space Telescope named for a scientist? Is a microscope used to shrink objects? Magnify your knowledge of microscopes...
Deciduous forest with moss covering fallen tree.
Moss, Seaweed, and Coral Reefs: Fact or Fiction?
Are most seaweed made of flowering plants? Are coral reefs mostly barren of life? Explore the underwater world of mosses,...
Artist's conception of closest known planetary system to our own Epsilon Eridani. Hosts two asteroid belts. The star is so close & similar to our sun thus popular in science by Issac Asimov, Frank Herbert, TV series Babylon 5.
Planets in Space: Fact or Fiction?
Is Uranus a solid mass of rock? Is Pluto considered a planet? Sort fact from fiction—and planets from planetoids—in this...
trees deciduous and coniferous. trees grow on a bank of a forest in springtime in Alberta, British Columbia, Canada. logging, forestry, wood, lumber, wilderness
Grasses and Other Plants: Fact or Fiction?
Can carnivorous plants eat humans? Is grass the plant type with the most species? Sort fact from fiction in this quiz.
11:058-59 Newton, Sir Isaac: An Apple, An Idea, portrait of Isaac Newton; apple falls from tree and hits him on the head; gravity of sun and planets
Physics: Fact or Fiction?
Was Isaac Newton inspired to think about gravity by watching an apple fall? From space-time to Einstein’s theory of relativity,...
black hole. gravitational lens. Artist's rendering of a black hole formed by the death of a massive star. gravity, gravitational pull, gravitational field
Galaxies and the Milky Way: Fact or Fiction?
Is Earth’s galaxy called the solar system? Is the largest galaxy in the Local Group the Milky Way? Sort fact from fiction...
Forklift truck. Illustration of a yellow fork lift truck for elevating or lowering a load. Construction, industry, transportation, lift truck, fork truck.
Engines and Machines: Fact or Fiction?
Is a gasoline engine more efficient than a diesel engine? Is a lever a machine? Rev up your knowledge of engines and machines...
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Science Subcategories

Neil Armstrong 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
subcategory placeholder 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
banded fire salamander (Salamandra terrestris) 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
microfauna 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
Crustal abundances of elements of atomic numbers 1 to 93. 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
Seed fern 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
Earth's 25 terrestrial hot spots of biodiversity 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
platypus 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
subcategory placeholder 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
Rafflesia flower 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
Schematic diagram of a flotation separation cell. 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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