Across
- 2. Unit of measurement of for power
- 4. When an object is moving away from us and its wavelength becomes longer
- 6. Astronomer who helped disproved geocentric by looking at the moons of Jupiter
- 7. The surface of the earth
- 11. Flow of charged particles
- 13. A type of wave where particles move back and forth in line line with the direction of the wave
- 14. This has the smallest wave length on the EM-spectrum
- 15. How good a device is at creating useful energy
- 20. The man who discovered ultraviolet
- 21. Change in direction of light
- 22. A type of wave that travels through the Earth
- 23. Astronomer who discovered infrared
Down
- 1. Light that we can see with the naked eye
- 3. The theory that the universe has always existed
- 5. The unit of measurement of frequency
- 6. The theory that all planets orbit around the Earth
- 8. The second stage in the life of a star
- 9. The system where planets orbit the sun
- 10. A change in the DNA caused by radiation
- 12. A type of wave where particles move at right angles to the direction the wave is moving
- 16. Sound waves that are bellow 20Hz
- 17. The colour that is best for absorbing heat
- 18. A type of lens that is curved on both sides to make it thicker in the middle
- 19. The number of waves passing through a point per second