NASA is currently planning out sending humans to Mars as soon as 2030. They have three major challenges they need to solve before we can send humans to Mars. First, they need to do a lot of research about how Humans react to a long time in space which they can conduct from the lab at the International Space Station. They also need to develop better thrusters so that they could shorten the travel time from Earth to Mars or to any other planet out there that we might want to go to. Finally, they need to get enough money and make the right partnerships so that they will be able to make it to mars without spending all the US government's money.