= 27d567bc2d48d9f40e9ccc20ea370b15)
army1987 comments on New Monthly Thread: Bragging - Less Wrong
You are viewing a comment permalink. View the original post to see all comments and the full post content.
= 783df68a0f980790206b9ea87794c5b6)
Loading…= b715d02e85f7b3b4ae65ca3d3e450868)
Subscribe to RSS Feed
Powered by Reddit
= f037147d6e6c911a85753b9abdedda8d)
You are viewing a comment permalink. View the original post to see all comments and the full post content.
Comments (145)
I've calculated that the atoms in the center of the Sun are not fast enough to escape the Sun's gravity even from its surface, let alone from its center.
And published it in my blog.
Not that it is a discovery of any kind, just another eyeopener how bad is our intuition.
Would you say, that 15 million K hot proton is too slow to escape the Sun's gravity?
Huh: Unless I've botched something:
kT for T = 15 MK is about 1.3 keV;
GmM/R for m = 938 MeV/c², M = 2e30 kg and R = 700,000 km is about 1.0 keV
(In retrospect, it's not surprising they would be the same order of magnitude, as per the virial theorem.)
(In the above I'm implicitly bragging about remembering the mass and radius of the Sun off the top of my head (everyone working in my field knows the proton mass anyway so that's not bragworthy), but I didn't learn them last month, so that doesn't count.)