| A | B |
|---|
| doppler effect | changing frequency of waves due to movement of source relative to observer |
| electromagnetic spectrum | the range of all possible EM radiation |
| multiple mirror telescope | telescope that uses many mirrors to increase its strength |
| reflecting telescope | telescope that uses mirrors to reflect light |
| refracting telescope | telescope that uses mirrors to bend light |
| optical telescope | any telescope that detects light |
| radio telescope array | a network of radio telscopes all linked together |
| visible spectrum | the part of the EM spectrum that can be seen by human eyes |
| absolute magnitude | measures brightness, taking into account its distance from earth |
| apparent magnitude | measures brightness without accounting for distance |
| astronomical unit (AU) | equal to the mean distance between sun and earth (150 million km) |
| Big Bang hypothesis | the theory that the universe originated from a very dense, very hot singularity |
| luminosity | the amount of energy a body radiates |
| nebulae | hugh clouds of cosmic dust and hydrogen and helium gases |
| supernova | massive explosion after a massive star collapses |
| neutron star | remnant of a massive star after going supernova |
| black hole | may from due to the collapse of a massive star |
| red giant | late stage of a average stars life; star with huge radius |
| main sequence stars | also known as dwarf stars, occur on diagnoal of Hertzsprung-Russell diagram |
| white dwarf | the "dieing" stage of an average mass star (like our own) |
| planetary nebulae | cast off outer layers of a red giant when it degenerates into a white dwarf |
| red dwarf | a small, relatively cool star (most stars are this) |
| blue giant | a very hot, very large main sequence star |
| quasar | very high energy (= 1 trillion suns) remnant of a neutron star |
| pulsar | rotating neutron star that emits EM radiation |
| kepler's laws | three laws that describe planetary motion |
| perhelion | time when earth is closes to the sun (January) |
| aphelion | time when earth is farthest from sun (July) |
| chromosphere | outer layer of sun, slightly red in colour |
| photosphere | layer of sun under chromosphere |
| sun spots | a dark cold spot on sun caused by magnetism |
| corona | a tasty mexican beverage, or the million km thick atomosphere of sun |
| solar wind | a stream of charged particles emitted by the sun |
| northern lights | caused by solar wind interacting with earths magnetic fields |
| elliptical orbit | oribt with two foci (ie planetary orbit) |
| inner palnets | also known as terrestrial planets |
| outer planets | also known as gas giants |
| meteoroid | a solid object in interplanetary space less than 50m across |
| meteor | meteoroid that has entered our atmosphere |
| meteorite | meteor that has hit earth's surface |
| asteroid | smaller bodies revolving around the sun (aka planetoid) |
| comet | object that orbits the sun has a "tail" of melted ice |
| perigee | when the moon is closest to the earth |
| apogee | when the moon is farthest from the earth |
| spring tide | highest tides when moon and sun pull together |
| neep tide | lowest tides due to sun fighting moons gravity |
| equinox | two times in year when earth's axis is not tilted towards sun |
| solstice | two times in year when earth is at its max. tilt towards sun |
| rotation | spinning on an axis |
| revolution | orbiting another object |
| zenith | when the sun reaches its highest point in sky |
| parallax | apprent movement of an object due to a change in observer's position |
