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.

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How Stephen Hawking Worked

He ventured to the abyss of black holes, wagered on the information paradox and floated around in zero gravity. Meet the man, the legend, the super scientist: Stephen Hawking.

By Marianne Spoon Famous Scientists / Physicists

How are frequency and wavelength of light related?

Frequency has to do with wave speed and wavelength is a measurement of a wave's span. Learn how frequency and wavelength of light are related in this article.

By HowStuffWorks.com Contributors Science Dictionary / Physics Terms

10 Cool Things You Didn't Know About Stephen Hawking

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 Famous Scientists / Physicists

How did the universe begin?

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 Science Dictionary / Astronomy Terms

What are dark matter and dark energy?

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 Science Dictionary / Astronomy Terms

Quasar

Quasar, or Quasi-stellar Object (QSO), a starlike object displaying an unusually large red shift.

Science Dictionary / Astronomy Terms

Magellanic Clouds

Magellanic Clouds, three irregularly shaped galaxies that lie some 150,000 to 200,000 light-years from earth.

Science Dictionary / Astronomy Terms

Nostradamus

Nostradamus, the Latin name of Michel de Notredame (1503-1566), a French astrologer and physician.

Famous Scientists / Astronomers

Cassini, Giovanni Domenico

Cassini, Giovanni Domenico (Jean Dominique) (1625-1712), an Italian astronomer. As a skilled observer using the most accurate telescopes available at the time, Cassini made many important discoveries about the planets of the solar system.

Famous Scientists / Astronomers

Flammarion, (Nicolas) Camille

Flammarion, (Nicolas) Camille (1842-1925), a French astronomer. He was the author of many popular books on astronomy, including The Atmosphere (1871), Popular Astronomy (1879), and Astronomy for Amateurs (1904).

Famous Scientists / Astronomers

Clark, Alvan

Clark, Alvan (1804-1887), a United States maker of astronomical lenses. Five times his firm, Alvan Clark & Sons, made the then-largest telescope lens in the world.

Famous Scientists / Astronomers

Cannon, Annie Jump

Cannon, Annie Jump (1863-1941), a United States astronomer. She had a long, distinguished career at Harvard Observatory, 18961940, and was one of the foremost women scientists of her time.

Famous Scientists / Astronomers

Antony Hewish

Hewish, Antony (1924-) is a British astronomer and astrophysicist, a scientist who studies the physical nature, origin, and development of the solar system, galaxies, and the universe.

Famous Scientists / Astronomers

Eddington, Sir Arthur Stanley

Eddington, Sir Arthur Stanley (1882--1944), a British astronomer. As chief assistant at the Royal Greenwich Observatory, 1906--13, he began his studies of the motion, internal structure, and evolution of stars.

Famous Scientists / Astronomers

Hall, Asaph

Hall, Asaph (18291907), a United States astronomer. In 1877 Hall discovered the two satellites of Mars, naming them Deimos and Phobos.

Famous Scientists / Astronomers

Lovell, Sir Bernard

Lovell, Sir (Alfred Charles) Bernard (1913-), an English astronomer. In 1946 Lovell demonstrated the validity of using the techniques of radio astronomy to study meteors.

Famous Scientists / Astronomers

Carolyn Shoemaker

Shoemaker, Carolyn (1929-) is an American astronomer. She has discovered more comets than any other living astronomer.

Famous Scientists / Astronomers

Cecilia Helena Payne-Gaposchkin

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.

Famous Scientists / Astronomers

Young, Charles Augustus

Young, Charles Augustus (1834-1908) was a United States astronomer noted for his spectroscopic studies of the sun.

Famous Scientists / Astronomers

Abbot, Charles Greeley

Abbot, Charles Greeley (1872-1973) was a United States astrophysicist and authority on solar radiation.

Famous Scientists / Astronomers

Mason, Charles

Mason, Charles (1730-1787), an English astronomer and surveyor. In addition to surveying the boundary between Maryland and Pennsylvania, Jeremiah Dixon and he fixed the precise measure of a degree of latitude in America.

Famous Scientists / Astronomers

Charles Messier

Messier, Charles (1730-1817), a French astronomer, discovered or independently codiscovered some 20 comets, earning him the nickname the “ferret of comets” by King Louis XV.

Famous Scientists / Astronomers

Clyde William Tombaugh

Tombaugh, Clyde William (1906-1997) was an American astronomer who discovered the dwarf planet Pluto.

Famous Scientists / Astronomers

David H. Levy

Levy, David H. (1948) is an amateur astronomer who helped discover the Shoemaker-Levy 9 comet.

Famous Scientists / Astronomers

Rittenhouse, David

Rittenhouse, David (1732-1796) was a United States astronomer and mathematician. Next to Benjamin Franklin, he was the most respected American man of science of his time.

Famous Scientists / Astronomers