In an op-ed for CNN, the president wrote that he hopes to one day look at the night sky with his grandchildren and tell them that humans are living on Mars.
If jets of water vapor are indeed erupting from Europa, a spacecraft could potentially fly through them and analyze their chemistry. The moon is believed to have a vast subterranean, saltwater ocean.
Flying people to an asteroid is really hard, so NASA wants to bring part of it to them. But some former astronauts say the $2 billion plan was born of politics and budget cuts, and makes little sense.
The mission aims to circle a hill-sized asteroid for two years, then skim its surface and bring a hearty sample of 4.5 billion-year-old dirt back to Earth.
Alex Longo hopes to be the first person to walk on Mars. In the meantime, the Raleigh, N.C., sophomore has suggested a landing site for the next rover mission. His pick is one of four finalists.
"It's bluer in color up there than other parts of the planet, and there are a lot of storms," a Juno mission leader says of the gas giant's northern reaches.
Six people spent that time living in a dome on a rocky volcanic plain on the island of Hawaii. The NASA-funded experiment was meant to simulate a long-term settlement on Mars.
Two American astronauts installed a new docking port that will allow astronauts traveling with private companies to enter the International Space Station.
Stargazers, get ready for something spectacular on Thursday. The annual Perseid meteor shower, already one of the most reliably impressive celestial events, promises to be especially good this year.