then theyd better find another planet to live on.-It will happen... in about 4.5 billion years,......
The Earth is currently shielded from harmful particles in the Solar Wind by the magnetic field of the Earth, and this magnetic field is generated by molten magma moving around under the surface of the Earth. If the magma stops moving around, then the magnetic field will disappear (or at least get much weaker), so then these harmful particle will be able to reach the surface of Earth and cause trouble for living things.
If humans still exist at that time, then they'd better find another planet to live on.
It will happen... in about 4.5 billion years, the sun will begin to swell, forming into a red giant. Mercury, Venus, and then Earth will be enveloped in the shell of the sun's atmosphere; prior to this, the temperature of the Earth will rise to the point of no longer being able to support life.... Friction with the solar atmosphere will cause our planet to slowly spiral in toward the sun's core, until tidal forces will essentially tear it apart, and rain down on the sun's surface.
I'll keep it simple. Once the sun starts to run out of hydrogen, it will begin to stop making energy. Gravity will take over, and the sun will shrink until the core is hot enough to fuse helium into carbon. This can take thousands to millions of years, so if life exists on earth, the deep freeze will likely kill it all. Then once the fusion begins, The sun will expand out to about 1 AU, the distance of earth. The earth will likely be completely engulfed.
