What happens to an object as its speed approaches the speed of light?

As an object's speed approaches the speed of light, a phenomenon known as relativistic length contraction occurs. According to the principles of special relativity, as an object moves faster and gets closer to the speed of light, its length in the direction of motion appears to decrease from the perspective of a stationary observer. This effect becomes significant as the object's velocity nears the speed of light, resulting in the contraction of space experienced by the object along its trajectory.

This contraction does not affect the dimensions of the object in a perpendicular direction to its motion; it is specifically related to the orientation of movement. The idea that the object becomes "heavier" is related to the concept of relativistic mass, but it is more accurate to speak of relativistic effects on momentum and energy rather than a change in its intrinsic mass. The statement about emitting more energy can be tied to the increase in kinetic energy, but it is not a direct result of the object's length contraction. The notion of invisibility does not have a basis in relativity and is not supported by experimental evidence. Thus, the correct choice focuses on the observable effect of length contraction occurring in accordance with relativistic principles as velocity increases towards the speed of light.