A NEEDLE HITTING THE EARTH AT THE SPEED OF LIGHT

With classical physics you would expect nothing to happen. The mass of an average needle is one gram, or around 0.001 kg. The mass of the Earth is an immense 5.9 × 10 to the 24th power kg. The needle is moving at the speed of light, or around 300,000,000 miles a second. The Earth is moving at a much lower speed of 30,000 miles a second. And if you use conservation of momentum, you will find that there is literally no reaction between the two. Although the needle is moving at such a high speed, the mass of the Earth is so comparatively immense. However, with relativity, as an object approaches the speed of light, its momentum approaches infinity. Because of this, it doesn't matter what the mass or velocity of the object the particle at the speed of light is striking, since it has infinite momentum, the collision will result in a massive loss of kinetic energy. And such a wave of kinetic energy, combined with the impact of the collision, will probably destroy the Earth and all life on the planet.