Across
- 3. an optical instrument that makes distant objects appear magnified.
- 5. Year a unit of astronomical distance equivalent to the distance that light travels in one year
- 8. Model the view that proposed the Sun as the center of the solar system.
- 14. Spectrum the range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies.
- 15. an imaginary line about which a body rotates.
- 17. System the gravitational bound system of the Sun and the objects that orbit it, either directly or indirectly
- 18. an astronomical body orbiting Earth as its only natural satellite.
- 19. Planet A celestial body resembling a small planet but lacking certain technical criteria that are required for it to be classed as such.
- 20. an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called out gassing.
Down
- 1. all of space and time and their contents
- 2. an object that has been intentionally placed into orbit.
- 4. a fixed luminous point in the night sky which is a large, remote incandescent body like the sun.
- 6. Model a superseded description of the Universe with Earth at the center.
- 7. Cloud a theoretical cloud of predominantly icy planetesimals proposed to surround the Sun at distances ranging from 2,000 to 200,000 au
- 9. Bang Theory the leading explanation about how the universe began
- 10. Calendar the calendar used in most of the world.
- 11. Belt 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.
- 12. the curved path of a celestial object or spacecraft around a star, planet, or moon, especially a periodic elliptical revolution.
- 13. a property of a physical body and a measure of its resistance to acceleration when a net force is applied.
- 16. an astronomical body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity