1,280 reputation
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bio website dotancohen.com
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age 37
visits member for 3 years, 4 months
seen 12 mins ago

Jun
18
comment Can a planet have a larger diameter than Jupiter?
I see, thanks. That sounds like a sound method.
Jun
18
comment Can a planet have a larger diameter than Jupiter?
That paper is a terrific read! I was able to finish it in under 5 minutes and I feel that I comprehended it all, even as a layman. I should read more papers from 1969!
Jun
18
comment Can a planet have a larger diameter than Jupiter?
Thank you Frédéric!
Jun
18
accepted Can a planet have a larger diameter than Jupiter?
Jun
18
comment Can a planet have a larger diameter than Jupiter?
Thank you Terry.
Jun
18
asked Can a planet have a larger diameter than Jupiter?
Jun
9
revised Can human push earth away from the sun?
added 81 characters in body
Jun
9
comment Can human push earth away from the sun?
Thank you for adding that, Anna. I have heard both arguments: that the Earth is approaching and that the Earth is receding from the Sun.
Jun
9
comment Can human push earth away from the sun?
Actually, there is nothing confusing about it. At the point in the orbit where you apply the acceleration the Earth will be moving faster. On the other side of the orbit the Earth will be moving slower, though. Of course, the distance from the Sun at that point will be larger, and that is where you see the extra energy. You can then perform a second manoeuvre at that slower, further point to push the opposite (closer, faster point) out further from the Sun.
Jun
9
awarded  Editor
Jun
9
comment Can human push earth away from the sun?
@Xiè: It is not a matter of efficiency but rather changing the shape (eccentricity) of the orbit and therefore the distance from the Sun (two manoeuvres). You should read the linked article on orbital mechanics.
Jun
9
revised Can human push earth away from the sun?
added 64 characters in body
Jun
9
comment Can human push earth away from the sun?
Thanks, Bill, you are right. The Sun will turn into a red giant, not nova. I'm all embarrassed now!
Jun
8
reviewed Approve Is it possible that I just saw Jupiter's moons?
Jun
8
comment Do any naked-eye stars have planets
Perfect! This is exactly what I was looking for. Thanks! The list does seem incomplete, thought as Fomalhaut is missing.
Jun
8
accepted Do any naked-eye stars have planets
Jun
8
answered Can human push earth away from the sun?
Jun
8
asked Do any naked-eye stars have planets
Jun
5
reviewed Approve Confusing description of Orions belt, could someone clarify?
May
13
comment Is the environment around an asteroid harsher than in interplanetary space?
Thank you. I suppose that you meant conduction, not induction, and I suppose that is possible. I know that lying on cold ground sure makes me cold. Thanks.