How old is our Sun and how long will it continue to shine?
Our Sun, which is 4.6 billion years old, is around halfway through its life. This was proven by the Big Bang theory that all of the solar system was made around the same time; therefore, moon rocks are around the same age as the Sun. So, all scientists had to do was study the moon rocks to discover approximately how old the Sun was. The Sun is an average star like many others in our galaxy; therefore, it has a lifespan of about 10 billion years. According to fact-based estimates, the Sun has about 5 billion years left to shine. At the end of its lifespan, the Sun swells up into a red giant, then “explodes” into a white dwarf, finally transforming into a dark dwarf.
Life Cycles of Stars with Different Masses:
The Life Cycle of a Small Mass Star (Our Sun) ~ Summarized
The Nebula: birthplace of stars
Protostar: a very young star that doesn’t have a fully developed, hot core to perform a fusion.
Main Sequence/Small star: Our sun is now in this stage; the core is burning hydrogen to helium and is fusing and giving off tons of energy.
Red Giant: fusion of hydrogen to helium decreases and slowly comes to a stop, causing it to burn helium to carbon, subsiding the core.
Planetary Nebula: layers of gas and dust after the red giant has lost all its hydrogen or exploded(nebula shaped like a ring or bubble).
White dwarf: exposed core which cools and becomes a black dwarf.
The Life Cycle of a Large Mass Star ~ Summarized
Nebula: birthplace of stars
Protostar: a very young star that doesn’t have a fully developed, hot core to perform a fusion.
Main sequence star: stars with larger masses still go through this stage, the stage of burning hydrogen to helium.
Red Supergiant: Like small mass stars, large mass stars can still expand into red giants due to their loss of hydrogen molecules, but from a large mass star, the red giant actually can burn out the last of its hydrogen and still grow about 100 times bigger.
Supernova: the explosion of such a large star is very violent and can cause many waves of shock, which later lead to the birth of another star: a neutron star!
Black Holes: A neutron star that’s made after a supernova explosion can be very dense; if it's slightly too massive, gravity will kick in and cause the neutron star to shrink into a deathly black hole. Nothing can escape a black hole, not even light.
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