Across
- 5. planets similar to Jupiter, large gas and low density
- 7. model of the solar system with the Earth at the center
- 8. the shortest type of electromagnetic radiation
- 12. the galaxy that we live in
- 14. young average stars like the sun
- 15. a change in wavelength caused by movement
- 17. everything known to exist
- 18. a spherical object that orbits a star
- 19. when a star moves towards us and its wavelengths are closer together
- 20. hydrogen molecules combine to make helium and release energy
Down
- 1. the brightness of a star compared to the sun
- 2. the cloud of gas and dust that stars form in
- 3. a collection of gravitationally bound stars
- 4. planets similar to earth, small rocky and dense
- 6. the idea that the universe began as a single point 13.7 billion years ago
- 9. this object orbits the Earth in both the geocentric and heliocentric model of the solar system
- 10. the star closest to the earth
- 11. when a star moves away from us and its wavelengths are further apart
- 13. gas and dust combining together into larger and larger pieces
- 16. model of the solar system with the Sun at the center