Astronomy Flashcards
Ptolemy
astronomer and mathematician. He believed that the Earth was the center of the Universe. The word for earth in Greek is geo, so we call this idea a “geocentric” theory.
Copernicus
astronomer, mathematician, translator, artist, and physicist among other things. He is best known as the first astronomer to posit the idea of a heliocentric solar system; a system in which the planets and planetary objects orbit the sun
Brahe, Tycho
a Danish nobleman known for his accurate and comprehensive astronomical and planetary observations. He was born in Scania, then part of Denmark, now part of Sweden
Kepler
described what later became known as the three laws of planetary motion in the early 17th century. His first and most famous discovery was that the planets move around the Sun in orbits shaped like ellipses
Galileo
an Italian astronomer, physicist, engineer, philosopher, and mathematician who played a major role in the scientific revolution during the Renaissance
Isaac Newton
an English physicist and mathematician who is widely recognised as one of the most influential scientists of all time and a key figure in the scientific revolution
Edwin Hubble
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
constellation in the northern celestial hemisphere. One of the 48 constellations listed by Ptolemy, it remains one of the 88 modern constellations
Ursa Minor
also known as the Little Bear, is a constellation in the northern sky. Like the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle
Orion
a prominent constellation located on the celestial equator and visible throughout the world. It is one of the most conspicuous and recognizable constellations in the night sky. It was named after Orion, a hunter in Greek mythology
Canis Major
a constellation in the southern celestial hemisphere. In the second century, it was included in Ptolemy’s 48 constellations, and is counted among the 88 modern constellations
Cassiopeia
a constellation in the northern sky, named after the vain queen Cassiopeia in Greek mythology, who boasted about her unrivalled beauty
Red Giant
A red giant star is a dying star in the last stages of stellar evolution. In only a few billion years, our own sun will turn into a red giant star, expand and engulf the inner planets, possibly even Earth
White Dwarf
also called a degenerate dwarf, is a stellar remnant composed mostly of electron-degenerate matter. A white dwarf is very dense: its mass is comparable to that of the Sun, while its volume is comparable to that of Earth
Main-Sequence Star
fuse hydrogen atoms to form helium atoms in their cores. About 90 percent of the stars in the universe, including the sun, are main sequence stars. These stars can range from about a tenth of the mass of the sun to up to 200 times as massive. Stars start their lives as clouds of dust and gas
