Across
- 5. artificial material that is orbiting Earth but is no longer functional
- 6. a celestial event in which a number of meteors are observed to radiate, or originate, from one point in the night sky
- 7. a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars.
- 8. an icy, small Solar System body that warms and begins to release gases when passing close to the Sun
- 9. a regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points
- 12. a small body of matter from outer space that enters the earth's atmosphere
- 14. fundamental system in condensed matter sciences and the main constituent of gas giant planets
- 15. a planet that is composed primarily of silicate rocks or metals
- 16. a meteor that survives its passage through the earth's atmosphere
- 17. composed mainly of hydrogen and helium
Down
- 1. a conic section is a non-negative real number that uniquely characterizes its shape.
- 2. a unit of measurement equal to 149.6 million kilometers, the mean distance from the center of the earth to the center of the sun.
- 3. circumstellar disc in the outer Solar System
- 4. solid objects thought to exist in protoplanetary disks and debris disks
- 6. a small body moving in the solar system
- 10. actual or apparent motion of a body in a direction opposite to that of the (direct) motions of most members of the solar system or of other astronomical systems with a preferred direction of motion.
- 11. A small planet
- 13. the area around a star where it is not too hot and not too cold for liquid water to exist on the surface of surrounding planets