The cosmic perspective Mid-term Flashcards

astronomy 101

1296920919	solar system	sun, planets, and all the other objects that revolve around the sun	0
1296920920	milky way	A large spiral galaxy that is home to Earth and the rest of our solar system, and about a trillion stars.	1
1296920921	galaxy	(astronomy) a collection of star systems	2
1296920922	universe	All of space and everything in it	3
1296920923	AU	average distance from the earth to the sun	4
1296920924	LY	average distance light travels in a year 10 trillion km	5
1296920925	mega LY	...	6
1296920926	Kilo light year	...	7
1296920927	Extrasolar planet	a planet orbiting a star other than the sun	8
1296920928	Constellation	A group of stars that form a pattern in the sky	9
1296920929	celestial sphere	Imaginary globe where Earth is at the centre and provides an easy way of describing position of objects in sky	10
1296920930	North celestial pole	Point directly over Earth's North Pole	11
1296920931	South celestial pole	point directly over Earth's South Pole	12
1296920932	celestial equator	an imaginary circle created by extending Earth's equator into space	13
1296920933	ecliptic	path of the sun and the planets	14
1296920934	zodiac	Constellations along the ecliptic	15
1296920935	equinox	Either of the two days of the year on which neither hemisphere is tilted toward or away from the sun.	16
1296920936	solstice	Either of the two times of the year when the sun is at its greatest distance from the celestial equator	17
1296920937	new moon	Moon phase that occurs when the Moon is between Earth and the Sun, at which point the Moon cannot be seen because its lighted half is facing the Sun and its dark side faces Earth.	18
1296920938	full moon	Looks like a ball. Has all light reflected	19
1296920939	waxing	(of the moon) pertaining to the period during which the visible surface of the moon increases	20
1296920940	waning	(of the moon) pertaining to the period during which the visible surface of the moon decreases	21
1296920941	gibbous	Moon phase in which more than half of the Moon appears to be illuminated.	22
1296920942	crescent	Moon phase in which less than half of the Moon appears to be illuminated.	23
1296920943	lunar eclipse	Earth blocks sunlight from reaching the moon	24
1296920944	solar eclipse	Occurs when the Moon passes directly between the Sun and Earth and casts a shadow over part of Earth.	25
1296920945	umbra	the exact shadow on the earth	26
1296920946	penumbra	shadow surrounding the distinctly sharp area of a shadow called the umbra.	27
1296920947	greenhouse effect	Anticipated increase in Earth's temperature caused by carbon dioxide (emitted by burning fossil fuels) trapping some of the radiation emitted by the surface.	28
1296920948	greenhouse gases	Carbon dioxide, methane, water vapor, and others are transparent to sunlight and trap heat radiating to earth back towards space.	29
1296920949	infrared radiation	Invisible energy felt in heat; has wavelengths longer than red light.	30
1296920950	carbon cycle	The organic circulation of carbon from the atmosphere into organisms and back again	31
1296920951	Ozone layer	Layer of the stratosphere with a high concentration of ozone; absorbs most of the Sun's harmful ultraviolet radiation	32
1296920952	scarps	Huge cliffs thought to have formed as the planet cooled and contracted	33
1296920953	lava basins	flat plains that have been paved due to lave from volcano eruption	34
1296920954	lunar maria	seas of cooled flat plains of lava from a puncture-not a volcano	35
1296920955	impact theory	the Moon formed from gas and debris thrown off Earth whe a Mars sized meteor struck it billions of years ago, the material orbited the Earth and coalesced to form the Moon	36
1296920956	dwarf planet	orbits the Sun; sphere shape; has not cleared the region of its orbit; not a moon	37
1296920957	kuiper belt	A region of the solar system that is just beyond the orbit of Neptune and that contains small bodies made mostly of ice	38