A 'runaway star' could save Earth from extinction a billion years from now. Here's how.

[Admin]

Earth will become too hot to handle in a billion years. There's a (very) remote chance a passing star could save us by knocking our planet back into the habitable zone.

A 'runaway star' could save Earth from extinction a billion years from now. Here's how. : Read more

 

[RikF]

Quote:

"the wandering star managed to gravitationally lure Earth away with it, capturing our planet in its free-wheeling orbit through the cosmos.

....could in principle end up on an orbit receiving enough energy for liquid water from our new home star."

How long would such a process take, before earth ends up in such a stable orbit around the new star? Would earth's axial tilt change? Would its rotational speed around its own axis change?

 

[Questioner]

The stable orbit of Earth or any planet around a single star is a really delicate balance between the star's gravity and the planet's inertia
on the satin surface of space.
A wild card passing star into that to randomly achieve a new stable and survivable orbit (for a bloated Sun) is so improbable to be just short of impossible.

The ability to manipulate massive bodies into desired orbits takes incredible energies and fine calculations as silken space continuously morphs throughout the process.
Billards, but on a frictionless stretching surface,
where in most cases you don't want the bodies to collide.

Fat chance.

 

[J.L. Bayer]

Earth will become too hot to handle in a billion years. There's a (very) remote chance a passing star could save us by knocking our planet back into the habitable zone.

A 'runaway star' could save Earth from extinction a billion years from now. Here's how. : Read more

I agree with the guy who suggested altering Earth's orbit as necessary. I believe it was somewhere on this site once where an author suggested that capacity could become ours in 50,000 years--which would be long before that envisioned megayear problem. Still, hooking up with another star might eventually make sense, though I'll gladly leave those details for others to figure out!