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 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?

What existed before the big bang?

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?

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.

Quasar

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

Magellanic Clouds

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

Nostradamus

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

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.

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).

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.

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.

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.

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.

Hall, Asaph

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

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.

Carolyn Shoemaker

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

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.

Young, Charles Augustus

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

Abbot, Charles Greeley

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

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.

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.

Clyde William Tombaugh

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

David H. Levy

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

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.

Rosse, Earl of

Rosse, William Parsons, Third Earl of (1800-1867), was a British astronomer and engineer.

Halley, Edmund

Halley, Edmund (1656-1743), was an English astronomer and scientist. He is best known for his studies of the comet that bears his name.


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