Science Dictionary
Do you know what a meteor is, or what scientists mean when they are talking about cryogenics? Our collection of science terms explains the meaning of some of the most common scientific ideas.
10 Scientific Words You're Probably Using Wrong
Can a planet float on water?
Can You Nominate Yourself for a Nobel Prize?
How Do You Win a Nobel Prize?
Quiz: How Much Do You Know About Stephen Hawking?
10 Cool Things About Carl Sagan
10 Cool Things About Neil deGrasse Tyson
How do polymer crystals work and why do they absorb so much water?
Is a Karat the Same as a Carat?
4 Quantum Physics Misconceptions, Busted
Chaos Is Not Randomness: A Complex Systems Scientist Explains
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The kilometer (km) is a standard unit of measurement used in the metric system. Derived from the French "kilomètre," the unit is used to measure length and distance along a straight path.
By Mitch Ryan
In any scientific research, there are typically two variables of interest: independent variables and dependent variables. In forming the backbone of scientific experiments, they help scientists understand relationships, predict outcomes and, in general, make sense of the factors that they're investigating.
By Marie Look
Physicist and cosmologist Stephen Hawking was a fierce spirit who symbolized the foibles and complexities inherent in human nature. Learn more about him by taking our quiz.
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The world often seems chaotic and events appear to occur randomly, but what's the difference between chaos and randomness?
How do scientists find details about the early days of our solar system? One way is to investigate comets. Find out how the Deep Impact spacecraft fired an impactor into Comet Tempel 1 to get some answers.
By Carolyn Snare
So much about galaxies remains a mystery. We know what they're made of and that we live in one (the Milky Way), but how many galaxies are in the universe?
While routinely scanning the stars, NASA scientists came across something they didn't expect to see: a vast area of space empty of stars, planets and matter.
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Scientists announced the discovery of the largest known planet in the universe. TrES-4 has a density similar to balsa wood, and some say this gas giant could float on water. Learn why this planet is so puzzling and how planet hunters make amazing discoveries like these.
He was born exactly 300 years after Galileo died. He never won a Nobel Prize, although he was awarded a guest spot on “The Simpsons.” What else do you know (or not know) about this acclaimed physicist?
By Jane McGrath
Every day, astronomers unravel a little more of the universe's inner workings, but the jury is still out on 95 percent of its contents.
By Robert Lamb
Berg, Paul (1926-), an American biochemist and molecular biologist, has been at the forefront of genetic engineering, both as an inventor of a pioneering procedure and as an advocate concerned about the risks of genetic research.
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You've heard of the big bang, of course, but do you have any idea as to what was happening during that massive flurry of activity billions of years ago?
By Robert Lamb
So much of our cosmological history starts with the much-discussed Big Bang, but what led up to that cataclysmic moment? And did time even exist back then?
Space collisions are the universe's car wrecks. Only in outer space, it's stars, asteroids and even galaxies doing the smashing.
By John Fuller
We take much for granted about our universe, like it's getting bigger. What if the universe stopped expanding and started collapsing inward with a giant crunch?
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Payne-Gaposchkin, Cecilia Helena (1900-1979) was a British-born astronomer who became an authority on variable stars (stars that change in brightness) and the structure of the Milky Way Galaxy.
Al-Tusi, Nasir al-Din (1201-1274) was one of the greatest scholars of his time and one of the most influential figures in Islamic intellectual history.
Aberration of Light is a phenomenon in which a star or other celestial body, as viewed from the earth, appears to be slightly displaced from its true position.
Chronometer, a timepiece that is exceptionally accurate. Traditionally, the term refers to the marine chronometer, a rugged mechanical instrument used at sea to keep time for navigational purposes.
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Cosmogony, the study of the origin and development of the universe as a whole and of the individual bodies that compose it.
Hourglass, a device for measuring time. In its usual form it consists of two cone-shaped or oval glass receptacles joined by a narrow neck.
Midnight Sun, a name given the sun when it can be seen at midnight during the Arctic or Antarctic summer.
The nebular theory, also known as nebular hypothesis, presents one explanation of how the solar system was formed, proposed by Pierre Simon de Laplace in 1796.
By Yara Simón
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Planetarium, is an educational device for showing the locations and movements of the planets and other objects in the universe.
Planetesimal hypothesis is a theory of the origin of the solar system. It was proposed by Forrest R.