# Gravitational atraction of fast object [duplicate]

Let's imagine a asteroid that travels with 0.99999999999999999c.

(I know it's impossible).

Anyway... Relativistic mass of such object would be almost equal to earth's stationary mass.

Now let's imagine that such object passes closely to me (assuming I'm immortal etc.). According to $F_g=GMm/r^2$ (Where M is relativistic mass of this asteroid and m is my mass) such an object would attract me.

So would I gravitate after it? Would I gain it's speed constantly falling on it? Or maybe it would just pulled me for a moment, but then I would return to my ol' good non-relativistic speed in "everyday reference system"?

Or maybe something else would happen? What happens with gravity of relativistic, NON ACCELERATINNG objects? (Let's assume that there's something that makes this asteroid speed constant).

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## marked as duplicate by Alfred Centauri, Brandon Enright, ACuriousMind, Kyle Kanos, AliJul 19 '14 at 6:12

This question was marked as an exact duplicate of an existing question.

"(I know it's impossible)". Why? Motion is relative. In the reference frame of a proton with a speed of $0.999... c$, relative to the asteroid (not impossible) it is the asteroid that has this speed. – Alfred Centauri Jul 18 '14 at 23:49
This is related to the question of whether or not an object can "move so fast" that it becomes a black hole. So I'm voting to close as a duplicate of physics.stackexchange.com/q/3436/9887 – Alfred Centauri Jul 18 '14 at 23:55
@AlfredCentauri Do I understand it properly that there wouldn't occur incerase in gravitational force. Not a single newton? I don't care about black holes. It's a shame, but I don't know much about general relativity. – user46147 Jul 20 '14 at 8:01
In relativity, gravity is not a force. The fact is simply this: the Newtonian gravitational force formula is fine in the low-speed, low mass-energy limit of general relativity. However, you're stipulating that the system is ultra-relativistic while, at the same time, using the Newtonian concept of gravitational force and the special relativistic (outdated) concept of relativistic mass. But that's simply not a valid way to think about this problem. – Alfred Centauri Jul 20 '14 at 12:34
@AlfredCentauri So I wouldn't feel even a tiny attraction? – user46147 Jul 20 '14 at 21:35