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Team Number: 081 School Name: Mosquero High Area of Science: Project Title: Death of the Sun Project Abstract: http://mode.lanl.k12.nm.us/97.98/abstracts/081.html Interim Report: http://mode.lanl.k12.nm.us/97.98/interims/081.html Final Report: http://mode.lanl.k12.nm.us/97.98/finalreports/081/finalreport.html
In doing so, we have been researching the lives of stars. The Sun is the Central body of the Solar System and the closest star. A star is alarge ball of hot gas, thousands to millions of kilometers in diameter, emitting large amounts of nuclear reactions in it's interior.
When stars like our sun die, they will become white dwarfs. White dwarfs are stars that are nearing the end of their lives. As a star runs out of fuel in its center it grows into a red giant. They are considered next-to-final stage in Stellar Evolution for stars less that 1.4 times as massive as the Sun, the final stage being black dwarfs, or burned_out stars.
White Dwarfs are the remnants of stars that were massive enough to stay alive using nuclear fusion in their cores, but not massive enough to blow apart in a Type IIa supernova.
The Death of our sun has been predicted to happen, but not for another 5 billion years. When it does happen, the inner planets, Mercury, Venus, Earth, and Mars will all be consumed by the sun's expanding surface. Then after a few million years the outer layers of the red giant will begin to puff of and form a planetary nebula. Leaving behind only the dead core of the star made mostly of carbon and oxygen.
A typical white dwarf is smaller than Earth, about the size of the United States. It is also very dense and hot. The star keeps itself from collapsing under gravity by quantum mechanical electron pressures rather than the thermodynamic pressures that keep most stars from collapse. A spoonful of white dwarf material on Earth would weigh as much as a car.
The red giant is a large bright star with a cool surface. It is formed during the later stages of the evolution of a star like the Sun, as it runs out of hydrogen fuel at its centre. Red giants have diameters between 10 and 100 times that of the sun. They are very bright because they are so large, although their surface temerature is lower than that of the Sun, about 2000-3000 degrees C. Very large stars are often called Super Giants. The diameters reach up to 1000 times larger than the sun.
Black dwarfs are the final phase of the Stellar Evolution of white dwarfs. This happens when the white dwarfs have exhausted their energy sources. Any light they produce after this is from gravitational contraction. The cold, dark hulks remaining when this energy is expended is called black dwarfs. Since they are small and give out no light, no black dwarfs have been discovered yet.