How long until the Sun becomes too big to support life as we know it?

Question

The Sun will live an estimate 5 billion years growing into a red giant and then collapsing into a red dwarf. However, well before this our Sun's increasing output of energy will boil away Earth's oceans. So, how long is it estimated until the Sun gets too big to support life as we know it?

I'm going to start the bidding at 2 billion years =)

Answer 1

You mean a red giant?

Answer 2

Neil deGrasseTyson estimates the sun will become a red giant in 4-5 billion years. Personally, I just can't wait that long !!!   lol

Answer 3

More than 1.4 billion years from now!

And the Sun will collapse into a WHITE dwarf!

Answer 4

Well... from what I understand, the sun will expand slightly over the years, but only when it begins to run out of hydrogen will it truly swell... I'd say it's going to be very stable right up to the point of the red-giant phase - say 4.5 to 5 billion years.

I could be wrong.... Nahhh.. I'm never wrong. : )

Answer 5

Let us put it this way.

First, following the main sequence path on Hertzsprung-Russel diagram, it expands as a Red giant becoming cooler in the process. Its expansion will gobble up the inner plants. When it reaches the size of Antares i(n Scorpio) it gobbles up Earth, in about a few billion years (we wouldn't be there to discuss that), evaporating the outer gas giant into cinders. Then it starts collapsing and depending upon the dynamics then may blow up many times spewing matter around. There is a theory that such a thing has happend once (may be several billions years ago). Evidence for that is the abundance of higher and heavier elements (of periodic table) that were the over-cooked remnants of super massive supernova.

Answer 6

The best guess is 2 - 3 billion years.

Answer 7

What a sad thought, our home along with all of our collective remains burning up until nothing is left.

p.s. I'm going to head on over to the religion forum now...

Answer 8

At best we've got no more than half a billion years left.

Reason:

There's a short window of about 1 billion years when it's possible for plants and animals to survive on Earth, and that's probably true of any habitable planet. We're already about half way through it.

To simplify a very complicated story about the "devolving" of planet Earth, Brownlee and Ward have reduced its 12-billion-year lifespan to 12 hours, with the end coming at high noon.

It's only 4:30 a.m. in Earth's "day in the sun," as they put it, but by 5 a.m. the 1 billion-year reign of plants and animals will come to an end.

By 8 a.m. the oceans will vaporize.

By noon it will all be over, about 7.5 billion years down the road.