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Every time I watch this TV program that discusses about all the facts about the universe , and it came to a point where they said that as an object approaches the speed of light the mass of the object increases and space decreases , my question is that if an object has very energetic particles in it like that of the sun then wouldn't its mass be higher hence making its gravity greater than that of the still state ones ?

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marked as duplicate by Ben Crowell, Waffle's Crazy Peanut, Qmechanic Jul 11 '13 at 23:57

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

possible duplicate of Does relativistic mass have weight? – Ben Crowell Jul 11 '13 at 16:44
Related: – Qmechanic Jul 11 '13 at 16:44
The speeds of the electrons, neutrons, and protons inside atoms, like the ones in the dirt at your feet, are about 1% of the speed of light, so you don't need to talk about the core of the sun to get such an effect. – Ben Crowell Jul 11 '13 at 16:44

Inertial mass of an object is pretty much constant. Relativistic mass can sound a bit misleading, but it really just refers to the relativistic momentum of an object in special relativity. So while an object moving fast with respect to an inertial observer has more relativistic mass than it would if it were at rest w.r.t. the observer, it's inertial mass ( which equals its gravitational mass ) stays the same.

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See the answers to the question linked under the original question: the gravitational effect does increase. – Kyle Oman Jul 11 '13 at 19:48

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