1		2					3
			4																				5
					6										7				8							9
		10
								11
			12												13
																	14
		15
					16
	17
18
				19							20
						21
								22
23

Across 2. a shift in frequency of acoustic or electromagnetic radiation (2 Words) 6. the device or material that a rocket carries 7. items in space that give off radio waves (2 Words) 10. a device for the movement of electrical charge 11. Study of data with respect to different spectral responses. (2 Words) 12. the entire range of wavelengths of electromagnetic radiation 15. a device that makes rainbows 16. a unit of measurement equal to 149.6 million kilometers, the mean distance from the center of the earth to the center of the sun (2 Words) 18. the ability of a microscope or telescope to measure angular separation of images that are close together (2 Words) 20. the branch of astronomy concerned with radio emissions from celestial objects (2 Words) 23. Every point mass attracts every single other point mass by a force pointing along the line intersecting both points (2 Words)

Down 1. a stage or multistage rocket (2 Words) 3. a kind of radiation including visible light, radio waves, gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously (2 Words) 4. The branch of science concerned with the investigation and measurement of spectra produced when matter interacts with or emits electromagnetic radiation 5. the sun, moon, stars, and planets (2 Words) 8. a lens that is attached to multiple different eyepieces, telescopes, binoculars etc. (2 Words) 9. A particular wavelength of light corresponding to an energy transition in an atom. (2 Words) 13. a plate of glass or metal ruled with very close parallel lines, producing a spectrum by diffraction and interference of light (2 Words) 14. the angle of horizontal deviation, measured clockwise, of a bearing from a standard direction 17. when the sun is at the centre of the solar system 19. when the earth is at the centre of the solar system 20. the fact or phenomenon of light, radio waves etc. being deflected in passing obliquely through the interface between one medium and another or through and medium of varying density. 21. a shift in the spectra of very distant galaxies toward longer wavelengths (2 Words) 22. A regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points