SPEED IS SELF-LIMITING

It is tempting to suppose that the mass of an object, if it could be accelerated all the way up to the speed of light, would become infinite. After all, as u approaches 1 (or 100 percent), the value of m in the preceding formula increases without limit. However, it’s one thing to talk about what happens as a measured phenomenon or property approaches some limit; it is another matter entirely to talk about what happens when that limit is reached, assuming that it can be reached.
No one has ever seen a photon at rest. No one has ever seen a space ship moving at the speed of light. No finite amount of energy can accelerate any real object to the speed of light, and it is because of relativistic mass increase that this is so. Even if it were possible, the mass-increase factor, as determined by the preceding formula, would be meaningless. We would have to divide by zero to calculate it, and division by zero is not defined in mathematics.
The more massive a speeding space ship becomes, the more powerful is the rocket thrust necessary to get it moving faster. As a space ship approaches the speed of light, its mass becomes gigantic. This makes it harder and harder to give it any more speed. Using integral calculus, astronomers and physicists have proven that no finite amount of energy can propel a space ship to the speed of light.