Astronomers and Stars Flashcards
Ptolemy
Greek astronomer and mathematician who based his astronomy on the belief that all heavenly bodies revolved around Earth. Ptolemy’s model of the solar system endured until the 16th century when Nicolaus Copernicus proposed that the heavenly bodies in the solar system orbited the Sun.
Corpernicus
a crater in the second quadrant of the face of the moon, having an extensive ray system: about 56 miles (90 km) in diameter from crest to crest with walls rising about 12,000 feet (3650 meters) from its floor; having several central mountains the highest being about 2400 feet (730 meters).
Brahe, Tycho
Danish astronomer whose observations of the planets provided the basis for Kepler’s laws of planetary motion (1546-1601) Synonyms: Brahe Example of: astronomer, stargazer, uranologist. a physicist who studies astronomy.
Kepler
German astronomer and mathematician who is considered the founder of celestial mechanics. He was first to accurately describe the elliptical orbits of Earth and the planets around the Sun and demonstrated that planets move fastest when they are closest to the Sun.
Galileo
Galilei Italian astronomer and mathematician who was the first to use a telescope to study the stars; demonstrated that different weights descend at the same rate; perfected the refracting telescope that enabled him to make many discoveries (1564-1642)
Issac Newton
English mathematician and physicist; remembered for developing the calculus and for his law of gravitation and his three laws of motion (1642-1727) Newton, Sir Isaac Newton.
Edwin Hubble
was an American astronomer who played a crucial role in establishing the field of extragalactic astronomy and is generally regarded as one of the most important observational cosmologists of the 20th century.
Ursa Major
a constellation that is the most conspicuous of the northern constellations, is situated near the north pole of the heavens, and contains the stars forming the Big Dipper two of which are in a line indicating the direction of the North Star —called also Great Bear.
Ursa Minor
contrasting with Ursa Major), also known as the Little Bear, is a constellation in the Northern Sky.
Orion
a constellation on the equator east of Taurus represented on charts by the figure of a hunter with belt and sword.
Canis Major
a constellation in the S hemisphere close to Orion, containing Sirius, the brightest star in the sky Also called the Great Dog. Latin: the greater dog.
Cassiopeia
Cassiopeia constellation is located in the northern sky. It was named after Cassiopeia, the vain and boastful queen in Greek mythology.
Red Giant
a very large star of high luminosity and low surface temperature. Red giants are thought to be in a late stage of evolution when no hydrogen remains in the core to fuel nuclear fusion.
White Dwarf
a small very dense star that is typically the size of a planet. A white dwarf is formed when a low-mass star has exhausted all its central nuclear fuel and lost its outer layers as a planetary nebula.
Main Sequence Star
A main sequence star is any star that is fusing hydrogen in its core and has a stable balance of outward pressure from core nuclear fusion and gravitational forces pushing inward.
