SPACE VOCABULARY

2. a region of the solar system beyond the orbit of Neptune, believed to contain many comets, asteroids, and other small bodies made largely of ice
3. The total amount of matter in an object
5. the region of interplanetary space between the orbits of Mars and Jupiter in which most asteroids are found
8. The most widely accepted and used civil calendar internationally.
11. a cloud of comets and other objects. Astronomers believe it is way beyond the orbits of Pluto and the Kuiper belt
15. space and time are two aspects of spacetime. Spacetime is curved when there is gravity, matter, energy, and momentum. E=mc^2
17. a celestial body moving in an elliptical orbit around a star
18. The branch of science that studies the stars, planets, and other objects in space
19. A natural satellite of a planet; an object that revolves around a planet
20. The distance the light travels in one year

1. A natural or artificial object that orbits another object in space
4. An imaginary line that runs through the middle of an object around which the object rotates; a line at the side or bottom of a graph
6. An optical instrument that makes distant objects appear larger and brighter using lenses or curved mirrors
7. All existing matter and space considered as a whole
9. The curved path of one object, such as a planet or a moon, around a central object, such as a star or planet
10. the collection of eight planets and their moons in orbit around the sun, together with smaller bodies in the form of asteroids, meteoroids, and comets
12. a celestial object consisting of a nucleus of ice and dust and, when near the sun, a “tail” of gas and dust particles pointing away from the sun
13. A large system of dust, gas, stars, and other celestial bodies that has a particular shape
14. any massive self-luminous celestial body of gas that shines by radiation derived from its internal energy sources
16. An explanation of the origin of the universe stating that it started small and expanded over billions of years