According to our current understanding of physics, an object moving at the speed of light (c) would experience a phenomenon known as time dilation, as predicted by Einstein's theory of relativity. As a result, from the perspective of a stationary observer, several interesting effects would occur:
Length Contraction: As the starship approaches the speed of light, its length would appear contracted in the direction of motion. This means that the starship would appear shorter in the direction of its motion as observed by the stationary observer.
Time Dilation: Time would appear to pass more slowly for the starship relative to the stationary observer. This means that while a certain amount of time passes for the stationary observer, less time would pass for the starship. This effect becomes more significant as the starship approaches the speed of light, and at the speed of light itself, time would appear to stand still for the starship.
Blue Shift: Due to the relativistic Doppler effect, the light emitted by the starship would be shifted towards the higher energy (blue) end of the electromagnetic spectrum. This means that the light from the starship would appear more blue-shifted as it approaches the speed of light.
Increased Energy: As the starship accelerates towards the speed of light, its energy would increase dramatically. The kinetic energy of the starship would become extremely large, requiring an enormous amount of energy to accelerate it further.
It's important to note that these effects are based on our current understanding of physics, and they become more pronounced as an object approaches the speed of light. However, achieving the speed of light itself is currently considered impossible for massive objects with non-zero rest mass, according to our current scientific knowledge.