Donald Trump wants humans on Mars in the next three years.
He is unsatisfied with Nasa's current plans, to get humans on the Mars in the 2030s, and wants people on Mars by the end of his first term, in three-and-a-half years.
At a push, he wants people on the planet by the end of his second term, which would come in 2025 if he were to be elected again. The President told the astronauts that they need to speed up to meet his target.
Nasa's plan of a mission to Mars by the 2030s was already highly ambitious. It has been funded through a bill that Mr Trump just recently signed into law, which the astronauts had to remind him of during the video.
President Trump made the request during a livestreamed chat with Peggy Whitson, an astronaut who just became the American who has spent the longest time in space. During that video, he spoke at length about his plans for space exploration, and of his hopes for private corporations to be involved in that work.
During the call, Mr Trump joked that he wouldn't want to go to the International Space Station, because it is flying around the Earth at 17,000mph. That is "about as fast as I've heard", and "I wouldn't want to fly" at that speed, but it's "what you do", he said.