Question #a226b

1 Answer
Oct 18, 2017

Till about 10^15 (1 quadrillion) years

Explanation:

The Sun will run out of fuel and will eject its layers in a planetary nebula in about 5 billion years, after 5 billion years, it will become a white dwarf .
But white dwarfs still give out SOME light and heat. The estimated time for the Sun to cool enough to become a black dwarf is about 1 quadrillion years or more, when it will no longer emit any kind of radiation and will be invisible to the naked eye.

But for the "color(blue)"us"" in the your question, the sun will become a red giant in 5 billion years and engulf Mercury and Venus.

But in 1 billion years or so, there will be 10% increase in the sun's brightness. That would be enough to wipe out all life on earth :(
( unless human beings find some way to alter it by leaving earth... or anything ).