SpaceX Starship
In September 2016, at the 67th IAC (International Astronautical Congress), Elon Musk talked about the ITS (Interplanetary Transport System). It was going to be  tall and  wide. The booster was going to have 42 Raptors, and the spacecraft was going to have 9 Raptors. Both the booster and spacecraft are made from carbon composites, and could launch many times. The ITS can carry humans to Mars and other places inside the Solar System. When the spacecraft enters Mars's atmosphere, it cools by transpiration. Transpiration here means the spacecraft flows propellant to the front side and evaporates the heat.