Space Review

2. Our galaxy
4. A "cool" colour of star
6. What AU stands for
9. The furthest planet from the sun
10. The 'death' of a star resulting in a neutron star or black hole
12. The epoch during which stars and galaxies formed
13. Incredibly small subatomic particles that make up protons and neutrons
16. The innermost part of any star
17. an object whose gravity is so strong that nothing, not even light, can escape
18. An alternative theory to the Big Bang
19. Separates the inner and outer planets
22. A measure of distance that describes how long it takes light from an object to reach where we are now
23. Happens at 10 million degrees Celsius
24. A huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity

1. When half the moon is illuminated, we call it the first or third this
3. The closest planet to the sun
5. Another name for the inner planets
7. Most commonly accepted theory on the formation of the solar system
8. CME, or...
11. One of these is the distance between Earth and the sun
14. A natural, rocky satellite orbiting a planet
15. Another name for the outer planets
18. A part of Earth's atmosphere that absorbs the sun's radiation
20. The least common type of galaxy
21. The main factor in determining what will happen to a star after it 'dies'