Life and Death of Stars

1. Then they blow themselves apart in a _______ supernova explosion.
8. But, these may be the most _________ stars that can burn for trillions of years.
9. This results in the formation of a warm clump of molecules referred to as the ________.
11. In 2019 it was announced that ________ had observed the brightest quasar in the early Universe.
12. The temperature in the cloud is ___ enough for the synthesis of molecules.
15. Even still, the lensed quasar is extremely compact and unresolved in images from optical ground-based _________________.
18. Next time you look up at the stars, remember, this is how they were ___________ and how they will die.
20. Over ____________ of years, the white dwarf cools and becomes invisible.
21. As it expands, the star first becomes a subgiant star and then a ____ giant.

2. The study of quasars provides fascinating insights into the ______________ of the Universe.
3. The elements made inside the supergiant (such as _______, carbon and iron) are scattered through space.
4. The iron fusion reaction ________ energy, which causes the core to collapse
5. Most of the star material is blasted away into space, but the core ________ into a neutron star or a singularity known as the black hole.
6. This reaction is exothermic; it gives off _____ heat than it requires and so the core of a main-sequence star releases a tremendous amount of energy.
7. All stars, irrespective of their size, follow the same 7 stage cycle, they start as a ____ cloud and end as a star remnant.
10. The mean temperature of the Tauri star isn’t enough to support nuclear _______ at its core.
13. After puffing off its outer layers, the star collapses to form a very _______ white dwarf.
14. The gas and dust become ______________ as a result of the extreme gravitational and frictional forces exerted on them as they fall into the black hole.
16. The core _______ and begins fusing carbon, once the helium fusion ends.
17. As the speed of light is _________, objects observed from Earth are seen as they were when the light we see left them.
19. Helium molecules fuse at the core, as the star _________.