1. An 1-21-18-15-18-1 is a glow in a planet’s ionosphere. AURORA

2. A 3-18-1-20-5-18 is a formation on a planet’s surface caused by a meteorite’s impact. CRATER

3. 12-9--7-8-20 is electromagnetic radiation that we can see.  LIGHT

4. 13-5-20-5-15-18-15-9-4-19 are small rocks in space. METEOROIDS

5. An 15-18-2-9-20 is the path of an object as it moves around another object. ORBIT

6. People see a 19-21-14-19-16-15-20 as a dark spot on the sun. SUNSPOT

7. A 3-15-13-1 is the dust and gas surrounding the nucleus of a moving comet. COMA

8. The gravity of a 2-12-1-3-11 8-15-12-5 is so strong that light cannot escape. BLACK HOLE

9. 7-18-1-22-9-20-25 is a mutual physical force which attracts two bodies. GRAVITY

10. The earth’s atmosphere effectively blocks out most 21-12-20-18-1-22-9-15-12-5-20 light. ULTRAVIOLET