Across
- 4. what remains when a supergiant star collapses into itself
- 6. says that the milky way isn't our only galaxy there's not just one universe
- 8. hot center of the nebula
- 10. Mercury,Venus, Mars, Earth
Down
- 1. what theory happened 13.7 billion years ago
- 2. we can only make hypothesis about this, but we know it is in space
- 3. how the star begins (cloud of gas and dust)
- 5. includes Jupiter, uranus,Saturn,Neptune
- 7. massive stars become this
- 9. a huge assemblage of stars