What will happen to earth in a million or billion years? (i know that we won’t be existing anymore but for the human generation)
Well, the answer is it is likely to be destroyed by the sun.
Why? Because The future of the planet is closely tied to that of the Sun. As a result of the steady accumulation of helium at the Sun’s core, the star’s total luminosity will slowly increase. The luminosity of the Sun will grow by 10% over the next 1.1 byr and by 40% over the next 3.5 byr. Climate models indicate that the rise in radiation reaching the Earth is likely to have dire consequences, including the loss of the planet’s oceans.
See http://en.wikipedia.org/wiki/Future_of_the_Earth for more information.
See the picture below for the earth’s picture when it happens.
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