<p>By &quot;last&quot; I'm not talking about survival of life. I know the Earth will be totally unlivable well before the sun swells into a red giant.</p>
<p>I'm talking about the whole planet being vaporized right down to the core.</p>
<p>It seems to me that the enormous thermal and inertial mass of the Earth might hold up against the hot (but not core-like hot) and tenuous outer layers of a red giant a fairly long time before being greatly ablated and slowed, but I have no idea how the numbers would work out even to a vague order of magnitude. Days? Years? Decades? Millennia?</p>
<p>Obviously the closer the Earth spirals in toward the sun the faster the process goes, but I have no clue how quickly that spiralling inward would happen, or how quickly the Earth would be shrinking as its outer layers are vaporized away.</p>

CC BY-SA 4.0
2024-08-06T04:28:42.667Z
What is your starting time for the process?  The whole process is rather continuous, so we would need to define a starting time.
Cort Ammon
CC BY-SA 4.0
2024-08-06T04:36:57.397Z
When the Earth makes contact with the surface of the expanding sun. I realize "the surface" might be a bit tricky to define, but if there's a standard definition for when the solar gases are considered dense enough to be "the surface", use that.
kshetline
CC BY-SA 4.0
2024-08-07T22:08:11.433Z
*Welcome to Astronomy SE!* Don't worry too much about some the comments above. I don't understand their purpose. This is a [tag:resource-request] question - you'd like to see what work has been one on this and perhaps to see what assumptions those authors made. I don't understand why the folks above are badgering you to about those details.
uhoh
CC BY-SA 4.0
2024-08-07T22:58:44.353Z
Does [this](https://astronomy.stackexchange.com/questions/48479/how-much-of-the-earth-would-remain-intact-if-the-sun-expanded-into-a-red-giant-e?rq=1) answer your question?
Lee Mosher
CC BY-SA 4.0
2024-08-08T01:28:26.790Z
@LeeMosher It certainly seems to; "Has anyone..." Yes!
uhoh
CC BY-SA 4.0
2024-08-09T01:55:27.697Z
I am marking your question as duplicate to [How much of the earth would remain intact if the sun expanded into a red giant encompassing its orbit?](https://astronomy.stackexchange.com/questions/48479/how-much-of-the-earth-would-remain-intact-if-the-sun-expanded-into-a-red-giant-e).
Nilay Ghosh
<earth><resource-request><red-giant>
Has anyone simulated how long the earth would last if/when engulfed by our sun turning red giant?
kshetline
# Has anyone simulated how long the earth would last if/when engulfed by our sun turning red giant?

(Asked by: username_0 on 2024-08-06)

By "last" I'm not talking about survival of life. I know the Earth will be totally unlivable well before the sun swells into a red giant.

I'm talking about the whole planet being vaporized right down to the core.

It seems to me that the enormous thermal and inertial mass of the Earth might hold up against the hot (but not core-like hot) and tenuous outer layers of a red giant a fairly long time before being greatly ablated and slowed, but I have no idea how the numbers would work out even to a vague order of magnitude. Days? Years? Decades? Millennia?

Obviously the closer the Earth spirals in toward the sun the faster the process goes, but I have no clue how quickly that spiralling inward would happen, or how quickly the Earth would be shrinking as its outer layers are vaporized away.

**Tags:** earth, resource-request, red-giant

> **Comments:**
> **username_1**: What is your starting time for the process?  The whole process is rather continuous, so we would need to define a starting time.  
> **username_0**: When the Earth makes contact with the surface of the expanding sun. I realize "the surface" might be a bit tricky to define, but if there's a standard definition for when the solar gases are considered dense enough to be "the surface", use that.  
> **username_2**: *Welcome to Astronomy SE!* Don't worry too much about some the comments above. I don't understand their purpose. This is a [tag:resource-request] question - you'd like to see what work has been one on this and perhaps to see what assumptions those authors made. I don't understand why the folks above are badgering you to about those details.  
> **username_3**: Does [this](https://astronomy.stackexchange.com/questions/48479/how-much-of-the-earth-would-remain-intact-if-the-sun-expanded-into-a-red-giant-e?rq=1) answer your question?  
> **username_2**: @LeeMosher It certainly seems to; "Has anyone..." Yes!  
> **username_4**: I am marking your question as duplicate to [How much of the earth would remain intact if the sun expanded into a red giant encompassing its orbit?](https://astronomy.stackexchange.com/questions/48479/how-much-of-the-earth-would-remain-intact-if-the-sun-expanded-into-a-red-giant-e).  

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