Across
- 5. brightness as it appears to us
- 7. supergiant star collapses into itself.
- 8. a well-known constellation.
- 9. a cloud of gas and dust.
Down
- 1. a star when fusion in its core occurs.
- 2. the intrinsic brightness
- 3. groups of stars.
- 4. huge assemblage of stars,
- 6. cools for eons until it is too admit