The sun’s red giant phase will happen when the time comes that it has depleted the hydrogen fuel in its core and, thus, will begin to expand. First, it will devour planets Mercury and Venus. At its largest, its surface will approximately reach the current orbit of Earth.
When that happens, what will happen to our beloved planet?
According to researchers, if we are really lucky,
then our orbit will expand out enough that it will miss the expanding sun and we won’t get incinerated.
“the heating Sun will evaporate the Earth’s oceans away, and then solar radiation will blast away the hydrogen from the water. The Earth will never have oceans again. It will eventually become molten again.
|The Sun contracts and continuous to expand, devouring Mercury and Venus.|
So to answer the question, life on Earth will essentially be wiped out when the sun becomes a red giant. It will become inhabitable that, before it happens, we have to find a new planet to call home.
But there’s no need to worry or panic over it now as the sun will not enter its red giant phase for another five to six billion years.