Across
- 3. the distance light travels in one year; about 9.46 trillion kilometers
- 6. the idea that the earth and the other planets revolve around the sun.
- 7. the brilliant explosion of a dying supergiant star
- 9. the sun and all of the planets and other bodies that travel around it
- 12. any of numerous small celestial bodies composed of rock and metal that move around the sun (mainly between the orbits of Mars and Jupiter)
- 13. An object that orbits the sun and is spherical, but has not cleared the area of its orbit. Pluto is a dwarf planet
- 18. a relatively small, rocky body that travels through space
- 20. The path of an object as it revolves around another object in space
- 22. a relatively large spherical body that orbits a star
- 24. A meteoroid that passes through the atmosphere and hits Earth's surface.
- 26. A large cloud of dust and gas in space
- 27. A unit of length used for distances within the solar system
- 28. A streak of light in the sky produced by the burning of a meteoroid in Earth's atmosphere.
- 29. space and all the matter and energy in it
Down
- 1. Provided more evidence for heliocentric theory of the solar system. He invented a new telescope, studied the sky, and published what he discovered.
- 2. a spherical region that surrounds the solar system, that extends from the Kuiper Belt to almost halfway to the nearest star, and that contains billions of comets
- 4. The name given to the four inner planets: Mercury, Venus, Earth, and Mars
- 5. Earth is the center of the Universe
- 8. A force of attraction between objects that is due to their masses.
- 10. This astronomer stated that the orbits of planets around the sun were elliptical, the planets do not orbit at a constant speed, and that an orbit is related to its distance from the sun.
- 11. a collection of stars, dust and gas bound together by gravity
- 14. ring of gases, ice, dust, and/or rock encircling a planet in a thin plane
- 15. A loose collection of ice and dust that orbits the sun, typically in a long, narrow orbit.
- 16. the theory that all matter and energy in the universe was compressed into an extremely small volume that 13 billion to 15 billion years ago exploded and began expanding in all directions.
- 17. Astronomer who proposed a geocentric system of astronomy that was undisputed until Copernicus (2nd century AD)
- 19. 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.
- 21. planets which have a thick atmosphere of gas and no solid surface, but they do have a solid core. Planets like Jupiter, Saturn, Uranus and Neptune are gas planets.
- 23. Devised a model of the universe with the Sun at the center, and not earth.
- 25. a large celestial body that is composed of gas and that emits light; the sun is a typical star