# The dreaded apocalyptic asteroid approaches Earth but lands 'safely' on the Moon [closed]

AT THE MOMENT I AM UNABLE TO DELETE - THE MODS HAVE BEEN ALERTED

An asteroid approaches and the Moon 'catches' it in the same way that a sports player catches a ball - that is to say by matching the velocity of the hand to that of the ball.

Could a lucky slingshot approach cause this to happen?

Assuming that the Moon has no atmosphere, my intuition tells me that there must be a direction and velocity such that an asteroid can do this. Does mathematics say otherwise?

In orbital mechanics and aerospace engineering, a gravitational slingshot, gravity assist maneuver, or swing-by is the use of the relative movement (e.g. orbit around the Sun) and gravity of a planet or other astronomical object to alter the path and speed of a spacecraft

https://en.wikipedia.org/wiki/Gravity_assist

• See it this way: since there are no aerodynamics involved, the whole process is entirely reversible. So you have to imagine an asteroid sitting quietly on the Moon's surface, then suddenly taking off and disappearing into deep space, just like that. Clearly this is not something you can imagine, and therefore the reverse is also not possible. Your best bet is that the asteroid comes in at a very shallow angle to the Moon, scrapes along its surface for a while, and eventually skip-stones to a halt without too much damage to it. – MichaelK Nov 29 '18 at 11:56
• I'm voting to close this question as off-topic because the author has already decided to move the question. – StephenG Nov 29 '18 at 12:00
• I have voted to close my own question. I'm getting a note saying I can't delete. I'm now stuck with both questions open. This has been reported to the mods by Mołot so hopefully it will get resolved. Apologies to all.– chasly from UK 22 mins ago – chasly from UK Nov 29 '18 at 12:06
• I've closed the question here for you @chaslyfromUK – Tim B Nov 29 '18 at 12:07
• It needs to be a very slow moving asteroid. and moving in precisely the right vector. That's the hardest part of your question as if getting the velocities right isn't hard enough. – a4android Nov 30 '18 at 1:38