The recent interstellar asteroid Oumuamua is the inspiration for this question.

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if a humanoid creature that had all the abilities to survive in space had hitched a ride on this asteroid and chose to jump off with enough power to reach earth at a high speed, what trajectory would the asteroid move in after the kick back force of the jump?

I want it to jump off with the asteroid in a similar position as the picture above (even though it was tumbling this suits the scene I want) but I want it to be at around 30 degree angle and the creature will be at the lower right end (see arrow) which would be facing earth, which could put the asteroid into a back spin when it jumps?

The asteroid will be between the point it was closest to earth and before it enters earths plane of orbit (yellow circle), preferably as close to earth as possible but not directly below earth because I want the view as it closes in to be of a well developed highly populated area of the world (haven't decided which yet but probably japan) and not a view of antartica and surrounding area.

so if a creature jumped off the asteroid with the conditions given how would this impact the trajectory of the asteroid, if any impact at all?


The creatures mass is that of an average human, I believe the asteroid was moving at around 49.67 km/s as it was under earth which was 41,317,365 km away. I may just use this figures and forget the scenic landing from another jump point, I am struggling with how fast the creature should get there as if it is fast that would make it ridiculously powerful and also will drastically affect what happens the asteroid.

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    $\begingroup$ This is just a math problem... You have the weight of your creature and how fast they need to move to reach earth versus the mass of the asteroid. Not really a world-building question imho. $\endgroup$ – Morris The Cat Aug 20 '19 at 15:49
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    $\begingroup$ Both momentum and angular momentum are conserved. $\endgroup$ – Zeiss Ikon Aug 20 '19 at 16:31
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    $\begingroup$ What is high speed? $\endgroup$ – L.Dutch - Reinstate Monica Aug 20 '19 at 16:38
  • $\begingroup$ You do know the monster will arrive here with at least 11km/s, but probably much higher speeds right? So I second L.Dutch in asking your definition of "high". $\endgroup$ – Renan Aug 20 '19 at 16:44
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    $\begingroup$ I wonder whether it would be feasible for the entity to jump off in such a way that they merely alter their orbit of the sun into an Earth intercept? If they jump at the right point, energy requirements could be minimal. $\endgroup$ – Arkenstein XII Aug 20 '19 at 20:57

I’d assume your humanoid has not enough mass and not enough muscles and energy to play a big role at all. On top of it some of the energy will be transferred into angular velocity. So even if it alters the asteroid course just so slightly it very likely will be not be enough to come back ever again as it is with the flying joint.

We are talking here 26km/s in reference to the sun and like several hundred-thousand kg ...to make a difference to. https://en.m.wikipedia.org/wiki/ʻOumuamua

The angular momentum might be another thing as you deliberately choose such nice jumping spot ..but again we are talking about a lot of mass here so my guess is that the induced rotation will be slow.

But here is the main question/problem

  1. the biggest problem i see is that the surface of that joint might be quite soft. A lot of energy will maybe be simply be absorbed by deformation when trying to jump of. This would need the likely false assumption that that asteroid (joint) is solid. But under the condition you are leaving the joint this seems not like a good assumption to make.
  2. Your are jumping off at the closest point what will ask for a speed that is ridiculous high because at the nearest point you have to overcome those 26 or 41 km/s.. so I rather see you destroying some of that joint before altering the course while maybe not even getting off safely.

The kinetic energy to accelerate to 41km/s is with 80kg human flesh is just 67 million kJ ... that not close to an atom bomb by a factor of 1000 but still a lot, but certainly not feasible.

In comparison 67GJ is equivalent to roughly 16 tons TNT what is maybe like 1/3 of the FOAB with 44 t TNT and quite close to MOAB with 11 t TNT.

https://en.m.wikipedia.org/wiki/TNT_equivalent https://en.m.wikipedia.org/wiki/Father_of_All_Bombs

Yet the joint is like 800x80x80m to 360x180x18m big. And the FOAB has a blast radius of 300m. If the man would put just 1/3 in that asteroid in a short moment ...I’m pretty sure the joint won’t hold together at the tip.

  • $\begingroup$ We talking the Hiroshima Bomb yield? $\endgroup$ – hszmv Aug 20 '19 at 18:50
  • $\begingroup$ Little boy had like 63TJ ..this human has to reach a kinetic energy of 67GJ. So yes Hiroshima Yield and a thousandfold less so probably like a conventional bomb like FOAB. $\endgroup$ – World Peace Aug 20 '19 at 19:05
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    $\begingroup$ I like to call this the Superman Problem. Can Superman pick up the Empire State building? No. It doesn't matter how strong Superman is, if you apply that much force to that small (Superman's hands) an area of the Empire State building, it just breaks. Ditto Aircraft Carriers, Supertankers, any of the Really Big Things they have him lift. $\endgroup$ – Morris The Cat Aug 20 '19 at 20:02
  • $\begingroup$ Good point Morris! $\endgroup$ – World Peace Aug 20 '19 at 20:07
  • $\begingroup$ good answer World peace thank you, good example Morris The Cat. $\endgroup$ – Aizen-sama Aug 21 '19 at 0:01

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