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If a massive body is moving at near light speed (or, hypothetically at light speed) and on course to hit Earth, will we feel its gravitational pull before it collides with us?

I think the answer is no because speed of gravity is same to speed of light.

Does it mean bodies moving at near light speed don't produce gravity?

From the comments>>>

if change of gravity propagates at the speed of light, and an object is moving at near light speed, does that change how much gravity there is ahead of that object?

Qmechanic
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user146021
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1 Answers1

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Yes they will feel the force of gravity. The fact is that even though gravitational field travels at the speed of light, it doesn't mean that the field only starts to act when the object is near the Earth, any massive object curves space time, and that curvature doesn't disappear. Due to the curvature the geodesic of the particle curves in slightly, and hence it is attracted by gravity of the object.

It too causes a curvature in spacetime. The point is that curvature depends on the amount of energy, momentum and their density in a region. So yes as it has both energy and momentum, we will feel it's attraction. But how much attraction, depends upon the object's mass and speed.

Entropy
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SK Dash
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