1. Groups of stars forming a recognizable pattern

1. Large round pits on the surface of a celestial body

2. An impressive or striking sight

3. The branch of astronomy that deals with the physics of celestial bodies

4. The dark shape of an object against a lighter background

5. Occurring or active at night

6. Observing stars and celestial bodies

7. Light from distant stars

8. Full of stars

9. Either of the two times of the year when the sun is at its highest or lowest point

10. The soft glowing light from the sky when the sun is below the horizon

11. A prominent constellation

12. A system of millions or billions of stars

13. The coming of darkness or night