Across
- 1. a cloud of gas produced when a red giant runs out of fuel
- 4. an almost massless, neutral particle released during some nuclear reactions
- 8. mass per unit of volume of a material
- 9. a now discounted theory that the universe has always existed in the form that it is in today
- 11. the force that causes all matter to collect together
- 14. a technique used to measure the distance to other stars
- 15. the theory that the universe began with a huge explosion
- 17. a measure of a star's brightness
- 18. two objects together
- 20. the stretching of light waves due to the motion of stars away from the observer
- 22. a large star
- 24. expansion or compression of waves due to the motion of the object making the waves
- 25. a cloud of gas found in the empty space between stars; birthplace of new stars
- 26. a giant explosion that occurs when star many times larger than our Sun runs out of nuclear fuel.
- 30. a really large star
- 32. a disk of gas surrounding a star that will form into planets
- 33. a small star
- 34. the process of dust and rocks slowly coming together due to gravity to form a larger object
- 36. the distance light travels in a year, 9500,000,000,000 km
- 37. very high frequency electromagnetic rays
Down
- 2. different types of electromagnetic radiation ranging from radio waves to gamma rays
- 3. a large group of stars attracted to each other via gravity
- 5. a positively charged electron
- 6. a collapsed star so massive that not even light can escape from its gravitational field; also called a black hole
- 7. a classification system for stars based on their colour
- 10. the force produced by radiation from pressure caused by heat
- 12. the bending of light rays due to the distortion of space caused by a massive object such as a black hole
- 13. a device that splits light into a spectrum to show its component wavelengths
- 16. the process in which hydrogen is converted into helium to produce light and heat
- 19. a black hole millions or billions of times the mass of our Sun, thought to be found at the centre of a galaxy
- 21. a range of electromagnetic
- 23. remnant of a supernova, consisting entirely of neutrons
- 27. the study of the history and structure of the entire universe
- 28. the galaxy in which our solar system in located
- 29. a collapsing cloud of gas that will eventually become a star
- 31. atoms with the same number of protons but different number of neutrons
- 32. an astronomical unit of length equal to 3.26 light years
- 35. state of matter consisting of positively charged ions and free electrons