I'm surprised both Hannah and Michael forgot how orbits work. Gravity pulls in. If Sol disappears the Earth moves tangential to the orbit we had. Not straight out. New distance when the Sun comes back is "only" about 1/cos( 3days / 1year) ~= 1.0013 of previous distance away. That's smaller than the current change in Earth-Sol distance over our orbit of about max = 1.05 * min.
At that distance I think the irradiance change would be about half of the current AGW energy imbalance (if I did the right math and lookup 0.9 vs 1.8 w/m2). You're only magically gaining potential energy in the Earth-Sol system so the new orbit isn't actually "the old orbit but 1.0013 away". It's something like 2/3rds of that change but with all the painful elliptical details left as an exercise to not me.
Um actually🧐, after making quick maths on paint:
yeah the earth would travel around 8 million km in the 3 days without Sun, but the tangent of the earths orbit at that scale its close to paralel with the real orbit (as you mention about gravity) it would "only" diviate 400.000 km from the current orbit. Given that the current orbit diviates 5 million km from apohelion to perihelion, its nothing. (Fun fact: the closer point to the sun is mid winter (for northen hemisphere))
So we may need to fix the calendar and recalibrate Gps satellites but no mayor extintions.
Crazy to me that Michael didn't remember that the 'She' of 'She sells seashells by the sea shore' was a real person, when he himself tolde that in his video 'How much is a bird in the hand worth?' 14 years ago when I was like 10
One note on Hannah's waste disposal ambitions: at orbital velocities, it's less energy to achieve escape velocity than it is to stop dead to fall into the central body. To drop nuclear waste into the sun, you'd need to cancel Earth's orbital velocity of ~30kps; to toss it into deep space, you'd only need to get it up to around 42kps.
A slight error in launching something into deep space will send it into a different bit of deep space; a slight error sending it into the Sun will have it whip past the Sun in a fast very elliptical orbit and fly back out again to around the same distance it started at...
to correct the 72 hour sun thing:
* The earth moves tangentially to its current orbit for 72 hours, and would return to an elliptical orbit when the sun returned.
* The new orbit would have an average distance of 150 million km from the sun (currently 149.6), a period of 366.7 days, and an eccentricity around 3 times what it is now.
* The perihelion would change to 142.3mil km from 147.1 and the aphelion would change to 157.7mil km from 152.1.
* The seasons would have much wilder temperature swings, but the average energy from the sun will only drop by 0.5%, so the temperature would only drop by 0.13%, corresponding to around 0.4C.
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At that distance I think the irradiance change would be about half of the current AGW energy imbalance (if I did the right math and lookup 0.9 vs 1.8 w/m2). You're only magically gaining potential energy in the Earth-Sol system so the new orbit isn't actually "the old orbit but 1.0013 away". It's something like 2/3rds of that change but with all the painful elliptical details left as an exercise to not me.
yeah the earth would travel around 8 million km in the 3 days without Sun, but the tangent of the earths orbit at that scale its close to paralel with the real orbit (as you mention about gravity) it would "only" diviate 400.000 km from the current orbit. Given that the current orbit diviates 5 million km from apohelion to perihelion, its nothing. (Fun fact: the closer point to the sun is mid winter (for northen hemisphere))
So we may need to fix the calendar and recalibrate Gps satellites but no mayor extintions.
A slight error in launching something into deep space will send it into a different bit of deep space; a slight error sending it into the Sun will have it whip past the Sun in a fast very elliptical orbit and fly back out again to around the same distance it started at...
* The earth moves tangentially to its current orbit for 72 hours, and would return to an elliptical orbit when the sun returned.
* The new orbit would have an average distance of 150 million km from the sun (currently 149.6), a period of 366.7 days, and an eccentricity around 3 times what it is now.
* The perihelion would change to 142.3mil km from 147.1 and the aphelion would change to 157.7mil km from 152.1.
* The seasons would have much wilder temperature swings, but the average energy from the sun will only drop by 0.5%, so the temperature would only drop by 0.13%, corresponding to around 0.4C.
"We can't just find fossils..."
"HANNAH FRY DID IT IN A CAVE...WITH A PILE OF SCRAPS!"