# Would impact angle matter on relativistic impactor?

I'm trying to calculate (for fun) a comparison between a kinetic impactor and an H-bomb.

I would assume this to be a fairly straight forward problem involving kinetic energy and a table of various H-bomb energy outputs. However, I was thinking about this and realized that assuming a fairly small mass (say 10kg) the velocity required would be approaching relativistic speeds.

I was thinking about this in the context of destroying asteroids, so I was also worrying about the impact angle and whether the target would absorb some of the energy by rotating about some axis. I decided that at the velocities involved and the energies released it would probably not matter.

However, I am not sure. Would "impact angle / distance from center of mass" be something I should worry about?

• Changed title, because I think I changed my question as I wrote it. – CoilKid Jul 14 '15 at 19:54
• It would only matter at the extremes, i.e. if the impactor only glanced off the planet and kept going with most of its kinetic energy. Otherwise the huge difference in momentum between even a relativistic 10kg object and the 6x10^24kg Earth means the primary interaction will be the deposit of the object's kinetic energy into the surface/atmosphere as heat. – Asher Jul 15 '15 at 0:45
• @Asher I was thinking more in the context of an asteroid. I was thinking that the energy difference would basically vaporize the asteroid or, if it didn't, just drill a hole through it and continue out the other side. I'd guess its the former, but I have no idea. – CoilKid Jul 15 '15 at 1:03
• I think I calculated the KE required to move a 100,000 ton rock to be insanely high. Anyway any thoughts would be helpful. – CoilKid Sep 4 '15 at 2:59