Sorry for the low quality. I can't upload anything bigger.
Sources
Comins, Neil F. "The Sun: Our Extraordinary Ordinary Star." Discovering the Essential Universe. New York: W.
H. Freeman, 2015. N. pag. Print.
H. Freeman, 2015. N. pag. Print.
"What Elements Are in the Sun? Ask a Chemistry Teacher." About.com Education. Web. 08 Oct. 2015.
"Windows to the Universe." Windows to the Universe. Web. 08 Oct. 2015.
You said our sun will become big enough to engulf the earth in about 7.5 billion years, is this caused from the amount of gravity the sun would then have at that large of a size? -Hailey Martinelli
ReplyDeleteThis is good question, and it could be very complex, because there are a lot of unknowns. The Sun is slowly expanding in size (very slowly), but it is not gaining mass. The Sun actually loses mass through solar wind, but expands due to a slight imbalance of the outward expansive forces of nuclear fusion and the inward forces of gravity. However, as the Sun runs out of hydrogen fuel through nuclear fusion, it will contract under the force of gravity, causing the core to have a massive temperature increase. This temperature increase at the core will cause the Sun to expand in its outer layers, which will eventually turn it into a red giant, which is a really, really big star. The heat from the red giant, and also it being closer to the Earth because of size (in fact, it will be just out of reach of the Earth's orbit now), will basically melt all the land on the Earth and evaporate the oceans.
DeleteBut, as I said before, there are a few unknowns. As the sun increases, it loses gravitational pull because of a loss in mass, which might result in the Earth flying away from the Sun into a larger orbit. That being said, it will still probably have enough gravity to pull us in and vaporize us. After that, the Sun will start turning the helium it produces now into carbon, and after that, it will become a white dwarf star.
Depressing, I know, but humans will probably never have to worry about this, because it's going to happen billions of years from now. Hopefully we'll have invented some sort of commercial space travel by then, right?