Across
- 2. core of a supermassive star that remains after a supernova; has gravity so strong that even light can't escape
- 4. theory a theory that says the universe began to expand with an explosion of concentrated matter and energy and continues to expand
- 6. huge collection of stars
Down
- 1. a tremendous explosion in which a star breaks apart, releasing energy and newly formed elements
- 3. imaginary vertical line through the center of a body around which the body rotates or spins
- 5. a huge cloud of dust and gas between the stars