Starlight and Science

4. A giant cloud of dust and gas in space; often a nursery for new stars.
5. A group of stars forming a recognizable pattern that is traditionally named after its apparent form or identified with a mythological figure.
7. The force that attracts a body toward the center of the earth, or toward any other physical body having mass.
9. A seemingly absurd or self-contradictory statement that may actually be true.
13. A band of colors, as seen in a rainbow, produced by separation of the components of light by their different degrees of refraction.
15. A completely empty space; the vacuum between stars.
17. An obscuring of the light from one celestial body by the passage of another between it and the observer.
18. The great size or extent of something; also a measure of the brightness of a star.
19. A system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.

1. Existing at or from the beginning of time; ancient and elemental.
2. A particle representing a quantum of light or other electromagnetic radiation.
3. Positioned in or relating to the sky, or outer space as observed in astronomy.
6. Electromagnetic radiation with wavelengths longer than those of visible light; heat radiation.
8. Either of the two times in the year when the sun reaches its highest or lowest point in the sky at noon.
10. The envelope of gases surrounding the earth or another planet; the thing that blurs our view of space.
11. The highest point reached by a celestial or other object; the point in the sky or celestial sphere directly above an observer.
12. A star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most of its mass.
14. An optical instrument designed to make distant objects appear nearer.
16. The curved path of a celestial object or spacecraft around a star, planet, or moon.
17. Lasting for a very short time; fleeting, like a mayfly or a moment.