Astronomy

4. The first stage in a star's life
6. When two objects move around each other
7. One of the two final stages in a high-mass star's life
9. The force that pulls objects together
11. A bright, distance galaxy that has a giant black hole in the middle
14. An object that has such a great gravitational pull that nothing can escape
15. All of space and everything in it
17. The explosion that expanded and formed the universe
19. The brightness of a star as seen from Earth
22. The building blocks of planets
24. The spinning motion of a planet on its axis
25. The distance light travels in one year

1. A rapidly spinning neutron star that gives off radio waves
2. The system model in which the Earth is placed in the center
3. The study of the moon, stars, and other objects in space
5. Where all stars begin their lives
8. The actual brightness of a star if it were at a standard distance from Earth
10. A system in which the sun is at the center
12. The explosion of a dying supergiant star
13. Matter that doesn't give off electromagnetic radiation
16. Made up patterns in the sky formed by stars
18. The apparent change of an object when seen from different places
20. The leftover core of a star from which the outer layers have drifted off into space
21. A large group of stars, star systems, star clusters, dust and gas bound together by gravity
23. When an object resists any change in its motion