You have probably heard that in five billion years the sun will turn into a red giant and swallow up the earth... Its a comfortably long time ...right?

But we are in trouble long before that :

Because Venus is made of pretty much the same stuff as our Earth, and has roughly the same size and mass, scientists are pretty sure that, back in the early days of the solar system, Venus was kind of nice. It probably supported liquid water oceans on the surface and white fluffy clouds dotting a blue sky. Actually, quite lovely.
But four and a half billion years ago, our sun was different. It was smaller and dimmer. As stars like our sun age, they steadily grow brighter. So back then Venus was firmly planted in the habitable zone, the region of the solar system that can support liquid water on the surface of a planet without it being too hot or too cold.
But as the sun aged, that habitable zone steadily moved outward. And as Venus approached the inner edge of that zone, things started to go haywire.
As the temperatures rose on Venus, the oceans began to evaporate, dumping a lot of water vapor into the atmosphere. This water vapor was very good at trapping heat, which further increased the surface temperatures, which caused the oceans to evaporate even more, which caused even more water vapor to get in the atmosphere, which trapped even more heat, and so on and so on as things spiraled out of control.
Eventually, Venus became a runaway greenhouse with all the water dumped into the atmosphere trapping as much heat as possible, with the surface temperatures continuing to skyrocket.
The liquid water that had been on the surface helped keep the tectonic plates nice and flexible, in a sense adding lubrication to the process of plate tectonics. But without the oceans, plate activity ground to a halt, locking the surface of Venus in place.

Plate tectonics play a crucial role in regulating the amount of carbon dioxide in the atmosphere. Essentially, carbon binds to elements in dirt and rocks, and those dirt and rocks eventually get buried far beneath the surface over the course of millions of years as the plates rub up against each other and sink below each other.
But without this process, carbon that was locked in the dirt just slowly outgassed or dumped out in massive volcanic events. So, once the oceans evaporated, the carbon problem on Venus became even worse with nothing to sequester it.

Over time, the water vapor in the atmosphere got hit by enough sunlight to break it apart, sending the hydrogen into space, with all that mass being replaced by carbon dioxide rising up out of the surface. And as that atmosphere grew thicker, the conditions on the surface grew even more hellish.
Once this process was complete, which probably took 100 million years or so, the potential for any life on Venus was snuffed out.
And here's the worst part about the story of Earth's twisted sister. This is our fate, too. Our sun isn't done aging, and as it grows older, it grows brighter, with the habitable zone steadily and inexorably moving outward.

At some point within the next few hundred million years, the Earth itself will approach the inner edge of the habitable zone. Our oceans will evaporate. Temperatures will spiral upward. Plate tectonics will shut off. Carbon dioxide will dump into the atmosphere.
And by that time, our solar system will be home to not just one hell but two. //

So life only have "a few hundred million years" left
before it must evacuate the earth or die out..

Thompson Olisaemeka Cajethan
Contact me via doncajethan@gmail.com