Astronomy Crossword

5. The second element in the periodic table
6. The largest type of black hole
8. The collapsed core of a massive supergiant star is known as this
9. One of Sir Isaac Newton's many discoveries
10. rotating disk of matter formed around a massive body
11. Massive, luminous ball of gas
14. The speed that an object needs to separate from an objects gravitational pull
17. The contraction of an astronomical object due to it's own gravity matter
18. The boundary defining the region of space around a black hole

1. The first element on the periodic table
2. All of space, and the matter and energy that resides in it
3. The boundary defining the region of space around a black hole
4. Two stars orbit around a common center of mass, both are bound to eachother
7. A region of spacetime where gravity is so strong nothing can escape
12. fusion the bonding of hydrogen and helium in the sun's core
13. A key part of the gravitational collapse of large stars
15. Occurs when a star explodes
16. Discovered that stars were destined to collapse into nothingness and form black holes