Astrophysics Edexcel IGCSE

5. Cosmic microwave background radiation.
6. A cloud in space made up of dust and gas.
7. A measure of how fast an object orbits.
9. The obeserved changes in wavelength and frequency of waves when object move relative to each other.
11. All the hydrogen has been used and larger nuclei are produced by fusion.
13. A body with sufficient mass and that orbits a star.
16. Man-made satellites that have been sent into space for satelite imaging and communications.
18. The stable sequence of all stars.
19. Objects made up of rock, dust and ice. As they travel close to a star they produce a long tail.
20. Statelites like moons which orbit planet.

1. The first stage all stars go throught aforming from a nebula.
2. The star will contract under gravity and cool down to form this object.
3. The observed increase in wavelength of light emmitted from distance galaxies.
4. A massive explosion of a star distributing elements created by fusion reactions.
8. -Russell diagram is a plot of the luminosity of stars against their temperatures.
10. The time taken for an object to complete 1 complete orbit.
12. A system containing billions of stars.
14. The currently accepted model for the origin of the known universe.
15. A orbital pathway that a satelite or planet may travel in around a star.
17. A change in this orbital pathway is needed for the body to undergo a speed change.
18. The galaxy in which our solar system is located.