BC: THE END | By WILLIAM HARPER
1: Learning my ABC of my Astronomy
2: Apogee: The point in an object's orbit around the earth when it is furthest from the Earth. | APOGEE
3: Black hole | A region of space around a very small and extremely massive object.
4: Chromosphere | Part of the Sun's atmosphere, it is visible during a total solar eclipse
5: Density | When our view of one object in the sky is blocked by either another object or the Earth's shadow. | The compactness of matter | Eclipse
6: Flares | Beautiful eruptions in the outer part of the Sun's atmosphere.
7: Galaxy | A group of stars, gas and dust held together by gravity. | Cloud of neutral hydrogen | HI region
8: Ionosphere | A region of the Earth's atmosphere. | Kelvin | A measurement of temperature often used in astronomy. 0 degrees Kelvin equals -273 degrees Celsius and -459.4 degrees Fahrenheit..
9: Lunation | Period between new moons. 29 days 12 hours 44 minutes.
10: Mass | Mass is the weight of something
11: Nova | A star which suddenly flares up to many times its original brightness before fading again.
12: Orbit | The path one object takes around another.
13: Planet | Quasar | A very distant, immensely bright object. | An object moving around a star.
14: Revolve | When something is moving in a circle around another object, such as the way the Moon Circles the Earth, | Saros cycle | A period of 18 years 11.3 days in which eclipses repeat themselves.
15: Troposphere | The lowest part of the Earth's atmosphere.
16: Umbra | The dark inner part of a sunspot, or shadow.
17: Variable stars | Stars which fluctuate in brightness.
18: Weather | Weather is the state that the atmosphere of a planet is in, like how hot or cold it is, or if there is precipitation (like rain).
19: Years | A planetary year is the length of time it takes that planet to revolve around the sun. | X-Ray Astronomy | X-ray astronomy studies celestial objects by looking at the x-rays that they give off.
20: ZENITH | ZENITH An observer's zenith is the point directly overhead.
21: Jupiter | I forgot J,W,X,Y | Jupiter is the largest planet in our solar system and the fifth planet from the sun