Theoretical basis of the movie "The Wandering Earth"

PowerAnts

Theoretical basis of the movie "The Wandering Earth" [Copy link]

The Roche limit is roughly equal to the sum of the radii of the two bodies, which means that even if the Earth is to break, it will be "broken" by falling into Jupiter rather than being torn into pieces.

yilonglucky

No, it is not "contact" or "collision". In short, it is assumed that the earth is two hemispheres stretched by a rubber band. Within the Roche limit, due to the different gravitational forces on the two hemispheres, the rubber band between the two hemispheres will be pulled apart or even broken. If these two hemispheres are expanded to n particles, the tearing described above will occur.

PowerAnts

yilonglucky posted on 2019-2-19 09:16 No, it is not "contact" or "collision". In short, it is assumed that the earth is two hemispheres stretched by a rubber band. Within the Roche limit, due to the two...

Have you calculated the Roche limit of Jupiter and the earth? The result I got is 56000km for rigid body and 108000km for fluid. The radius of Jupiter is 71392km and the radius of the earth is 6378km. The rigid body distance of the Roche limit is less than the sum of the radii of the two planets, so even if there is a direct collision, the Roche limit will not take effect.

PowerAnts

Please note that both planets should be considered as point masses and the distance of force should take into account the radius.

topwon

Jupiter is a gaseous planet, and I don't know whether it has any impact on the calculation results.

零一春风数声

:time:Do some research!