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Strange-Ad1209 t1_ixgvgom wrote

Reply to comment by CompellingProtagonis in Do you agree with Stephen Hawking about Earth being unsustainable? by yaykarin

Longer than that before it swells to a Red Giant and even then the Earth's orbit will once again shift as it has in the past many times from the mostly circular orbit it has for the last 5 million years to a highly elliptical orbit because of Jupiter and Saturn, Venus pushing and pulling as they have in the past causing the Ice Ages that have come and gone every 50,000 years or so then add in the strings of massive Asteroid impacts every 12,000 years that we are long overdue for.

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CompellingProtagonis t1_ixgvw7g wrote

It doesn't need to swell into a red giant for the earths oceans boil away. The sun slowly burns hotter and hotter as the proportion of helium to hydrogen increases. When the sun first formed it was something like 75% the brightness, and has slowly increased in brightness.

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Strange-Ad1209 t1_ixgw91a wrote

Yes but that may be an advantage for some of the life when Earth's orbit once again becomes more elliptical as it has done several times (3 periods of Snowball Earth over last 3 Billion years). Granted Humans won't like it or survive it above ground but many other forms of life, especially reptiles will absolutely love it. 8-)

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