when is the sun estimated to burn out?

Answer 1

The Sun, in 4.5 billion years supposedly, WILL start to swell. It will get bigger, and en-gulp Mercury and Venus. The atmosphere will evaporate, water will melt, and life will be gone. The sun will swell enough to devour the earth, then shrink, grow, Turn into a planetary nebula, then shrink, for the last time, into a white dwarf. Then In a few billion years, cool down to a black dwarf.

The reason the sun expands, In case you want to know, Is because of its fuel supply. The energy from the sun comes from nuclear fusion of Helium. When the helium supply runs out, The sun has to fuse hydrogen, therefore making the sun swell. The sun then will Shrink, once its helium supply is restored, grow again, then cast out a planetary nebula (For what a planetary nebula looks like, Look up the ring nebula) then it wont have enough hydrogen to grow back to the normal size...and become a white dwarf. Eventually, it will cool into a black dwarf and die.

And no, incase someone posts it, the sun will not become a black hole.

Answer 2

The sun will burn out (use up it's fuel of hydrogen) in about 5 billion more years. At present the sun is about 4.55 billion years old and it is in its main sequence. The main sequence of a star is when that star is stably burning hydrogen into helium. Once the sun has burned up its supply of hydrogen it will greatly expand, becoming a red giant, and will encompass Earth, roasting it, and then our sun will shrink down into a small white dwarf sun and then continue to burn less prominently for a few more billion years.

Answer 3

In 5 billion years

Answer 4

The sun we are havinng as the centre of our solar system is a middle size star in the universe. It's 1/4th the size of the nearest star to earth (other than sun) called 'Century'.
Our SUN has completed it's half life and it'll die after white Dwarf stage,approximately after 4 billion years.
It'll never turn into 'Black Hole' due to it's size.
Actually Sun gives us energy when the Hydrogen present undergoes 'Nuclear Fusion' reaction, it produces tremendous amount of energy when H-atoms combine to form Helium atom.
Other larger stars after burning up all the Hydrogen, starts a fusion reation in He-atoms chaning them to Carbon.
which finally turnsthe Star into 'Black Hole' towards its end.
But since our Sun is small is a medium size star it can't go to that level of energy and ca't sustain another fusion reation with He.
(Although some Fusion of Helium also occurs with that of Hydrogen, but in small fractions)

Answer 5

The sun is estimated to be at the midpoint of its life span right now. Dont worry, you got plenty of time...about another 4.6 billion of years left so we will be long gone before then

Answer 6

3-5 billion years

Answer 7

it will burn out in 5 billion years

Answer 8

4-5 billion years.

Answer 9

Several years after Al Gore goes mute.

Answer 10

3 billion years.