## NASA’s Webb finds signs of Mars-sized worlds smashing together Scientists think one of the most important events in the early solar system was a colossal collision between the young Earth and a Mars-sized body known as Theia. The impact likely vaporized huge quantities of rock and hurled material into space. Some of that debris eventually came together to form the Moon, where NASA's Artemis program is returning humans, preparing for Mars, and shaping the future of space exploration. That ancient impact dramatically altered Earth. Now, astronomers are using NASA's James Webb Space Telescope…