Across
- 3. A unit of astronomical distance equivalent to the distance that light travels in which is about 6 trillion miles per year.
- 5. The star around which the earth orbits.
- 7. A fixed luminous point in the sky that is a large, remote incandescent body like the sun.
- 8. A system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.
- 9. The natural satellite of the earth, visible by reflected light from the sun.
- 10. The collection of eight planets and their moons in orbit around the sun.
- 11. The degree or intensity of heat present in a substance or object.
Down
- 1. A celestial body moving in an elliptical orbit around a star.
- 2. The universe originated billions of years ago in an explosion from a point of nearly infinite energy density.
- 4. The intrinsic brightness of a celestial object.
- 6. All existing matter and space considered as a whole.