Across
- 3. - The percentage of incoming sunlight that a surface reflects.
- 6. - The outermost solid layer of Earth.
- 7. - The amount of mass in a given volume.
- 12. - The amount of open space within a material.
- 16. - The thick layer of rock between Earth's crust and core.
- 17. - Earth's rigid outer layer consisting of the crust and upper mantle.
- 18. - The lowest layer of Earth's atmosphere where weather occurs.
- 20. - The formation of new elements within stars through nuclear reactions.
- 23. - A measure of how elliptical an orbit is.
- 24. - The movement of tectonic plates away from each other.
- 31. - A red supergiant star located in the constellation Orion.
- 32. - The slow change in the direction of a rotating object's axis.
- 35. - The settling of transported sediments.
- 37. - The outermost layer of the Sun's atmosphere.
- 40. - A massive stellar explosion that occurs at the end of some stars' life cycles.
- 41. - A rocky object that orbits the Sun.
- 42. - The process in which atomic nuclei combine to form a heavier nucleus and release energy.
- 43. - The movement of tectonic plates toward each other.
- 44. - The path an object follows around another object due to gravity.
- 46. - All of Earth's water, including oceans, lakes, rivers, and groundwater.
- 48. - An underground layer of rock or sediment that stores and transmits water.
- 50. - A piece of rock or metal from space that reaches Earth's surface.
Down
- 1. - A large mass of moving ice formed from accumulated snow.
- 2. - The ability of a material to allow water to pass through it.
- 4. - The layer of gases surrounding a planet.
- 5. - The process in which one tectonic plate sinks beneath another.
- 8. - The layer of the Sun's atmosphere located above the photosphere.
- 9. - The atmospheric layer above the troposphere that contains the ozone layer.
- 10. - The lightest and most abundant element in the universe.
- 11. - The movement of an object around another object.
- 13. - The tilt of a planet's rotational axis.
- 14. - A large collection of stars, gas, dust, and dark matter held together by gravity.
- 15. - The solid Earth, including rocks, soil, and Earth's interior.
- 19. - All space, time, matter, and energy that exists.
- 21. - An icy object that develops a tail when near the Sun.
- 22. - The force of attraction between objects with mass.
- 25. - Energy that travels through space as waves or particles.
- 26. - The breakdown of rocks into smaller pieces.
- 27. - The shortening of light toward shorter wavelengths as an object moves closer.
- 28. - The soft, plastic-like layer beneath the lithosphere.
- 29. - The movement of water into the ground.
- 30. - The transfer of heat through the movement of fluids or gases.
- 33. - The variety of living organisms in an area.
- 34. - The spinning of an object on its axis.
- 36. - The rapid expansion of the universe immediately after the Big Bang.
- 38. - An element produced by fusion in stars.
- 39. - The range of electromagnetic wavelengths emitted or absorbed by an object.
- 45. - The visible surface layer of the Sun.
- 47. - The transport of weathered material by water, wind, ice, or gravity.
- 49. - The stretching of light toward longer wavelengths as an object moves away.