If you look up some references of the Shoemaker-Levy comet impact on Jupiter you find that they know the speed of impact and therefore the energy imparted to Jupiter because the speed was the same as the escape velocity of Jupiter. This is a fact derived from energy conservation.
Cometary impacts to the Sun are even greater energy because the much greater escape velocity of the Sun is the speed at which they impact the Sun.
The escape velocity is the speed at which the impactor would hit the red giant star. Calculate this for a red giant. You'll find it's in the thousands of km/s range.
Momentum conservation requires that that very high speed the impactor has just before impact gets converted into speed of the star after impact.
Bob Clark
Space/Science » in reply to escape velocity has nothing to do with it, and again you ignore momentum
Escape velocity equals the velocity of impact, it's BECAUSE of momentum the star must be imparted with additional velocity.
The whole thread (29 posts)
- From GALEX: Speeding-Bullet Star Leaves Enormous Streak Across Sky
- Speed due to planetary impacts?
- no: conservation of momentum - relative masses. (n/t)
- Yes, by conservation of momentum and relative speed.
- No
- to the extent that a body is accelerated by falling into a red dwarf...
- re: to the extent that a body is accelerated by falling into a red dwarf...
- Yes, by conservation of momentum and relative speed.
- no: conservation of momentum - relative masses. (n/t)
- My local affiliates...
- re: From GALEX: Speeding-Bullet Star Leaves Enormous Streak Across Sky
- re: From GALEX: Speeding-Bullet Star Leaves Enormous Streak Across Sky. - Of course a 'bow shock' is seen. (n/t)
- Speed due to planetary impacts?