Asteroid Alert

2. The region in space between Mars and Jupiter where many asteroids orbit
4. An object such as an asteroid or comet whose orbit brings it close to Earth
7. A method used to estimate the age of a rock layer by comparing it to layers above and below
10. A term used to describe something that has the characteristics of a gas
11. The property that describes how bright an object in space appears from Earth.
13. A lump of frozen gases, rock, and dust that orbits the Sun
15. A small piece of rock or ice that has broken off an asteroid or comet
16. A bright streak of light seen when space debris burns up entering Earth’s atmosphere
17. A meteoroid that has passed through Earth’s atmosphere and hit the ground

1. The property that measures how bright an object would appear if it were a standard distance away
3. Object, An object in space—such as a star or planet—that exists naturally in the Universe
5. A natural phenomenon in which something shines light back rather than absorbing it
6. The curved path a planet or object takes as it travels through space
8. A system of millions of stars, gas, and dust held together by gravity
9. A rocky object that orbits the Sun, smaller than a planet
12. A large, spherical object that orbits a star
14. The group of planets and moons that orbit the Sun.