Astronomy

5. diameter of the primary lens or mirror of a telescope
7. the apparent annual path of the Sun on the celestial sphere
8. any of the systems of stars and interstellar matter that make up the universe
11. an astronomical object consisting of a luminous spheroid of plasma held together by its own gravity
13. instrument for collecting visible-light or other electromagnetic radiation
14. the study of the organization and evolution of the universe
15. the study of everything in the universe beyond Earth's atmosphere
18. the gravitationally bound system of the Sun and the objects that orbit it, either directly or indirectly.

1. a large mass that revolves around a star
2. centered on the Sun
3. the apparent displacement of a nearby star that results from the motion of Earth around the Sun
4. centered on Earth
6. complete or partial obscurity of a celestial body by another
9. the pseudoscience that deals with the supposed influences on human destiny of the configurations and locations in the sky of the Sun, Moon, and planets
10. cosmic snowballs of frozen gases, rock, and dust that orbit the Sun
12. the point on the celestial sphere opposite the direction of gravity; point directly above the observer
16. a celestial body that makes an orbit around a planet
17. rocky worlds revolving around the sun that are too small to be called planets