The death of average stars:
Once a star has completely run out of hydrogen and helium gas, it becomes a white dwarf star. It changes into a white dwarf as it doesn't have the mass to endure another nuclear fusion reaction. Although, a white dwarf continues to shine as it once was an extremely hot star. Over billions of years a white dwarf will lose its heat and light and become a black dwarf which is simply a star which has cooled efficiently and no longer emits heat or light. Although this theory is undecided as scientists are yet to prove this true. The death of massive stars: After burning fuels as a red super giant for billions of years, massive stars will explode in a reaction called supernova. Following the explosion it injects carbon, oxygen and silicon into interstellar space. These enriched gases are incorporated into future generations of stars and planets. Without the fiery death of massive stars, there would be no carbon and oxygen to make life possible. These interstellar particles can then evolve and shrink into deadly black holes. Black Holes: What is a black hole and how do they form? A black hole is a place in space where gravity pulls everything in a certain space that even light cannot escape. This gravity is so strong because matter has been squeezed into a small space. A black hole generally occurs after a supernova. Scientists believe the smallest black holes were formed when the universe began (the big bang theory). How big is a black hole? The mass of a black hole can range between one atom to masses that are more than four million suns put together. Scientists have discovered that every galaxy has one super massive black hole (largest black hole). The super massive black hole within the milky way is called Sagittarius A. This black hole has a mass equal to about four million suns. How can we see a black hole? Scientists can see black holes due to the strong gravity effects on stars and gas around it. Scientists can also study stars to find if they are orbiting a black hole. |
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