Can you see an object approaching c grow?

[swansont]

If you want to calculate the energy an object has, or energy it needs to do something, that answer is valid only in the frame in which you do the calculation.

 

You have your planet, and a rocket out in space, initially at rest with respect to each other. The planet's mass is 10^25 kg, and the rocket's is 10^3 kg. The rocket fires, and starts moving at 1 m/s. It now has 500 Joules of energy. But someone in the rocket sees that planet moving, and having 5 x 10^24 Joules of energy — but the two numbers were calculated in different reference frames. You can't compare them. So your analysis in the first part of post 21 is invalid.

 

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Two protons moving at .99c with respect to me. In their own frame are at rest with respect to each other.

 

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Never use relativistic mass. It rapidly leads to confusion.