NASA has just announced something big, something that marks a huge development in the question to send mankind to Mars and maybe even beyond: they’ve wrapped up a feasibility study and have decided not to have any crew fly on the first flight of Exploration Mission 1 (EM-1) and the Space Launch System (SLS) and the Orion spacecraft, which will eventually carry astronauts to Mars in the coming decades. It’s a blow, as NASA had been hoping to make it a manned mission, but the studies ultimately decided that the time just wasn’t right yet.

It was back in February when NASA officials Acting Administrator Robert Lightfoot announced that he had asked William Gerstenmaier, associate administrator for NASA’s Human Exploration and Operations Mission Directorate in Washington, to start the study, and now that it’s been completed, the agency decided to go with the less risky unmanned version of Exploration Mission 1 (EM-1).

A crewed version of EM-1 may take place in 2019, but that would be the most recent, Lightfoot says. The launch would more likely take place in the first or second quarter of 2020, he said.

“NASA is assessing the feasibility of adding a crew to the first integrated flight of the agency’s Space Launch System (SLS) rocket and Orion spacecraft, Exploration Mission-1 (EM-1),” NASA said in the February statement. “NASA is building new deep space capabilities to take humans farther into the solar system than we have ever traveled, and ultimately to Mars. Acting Administrator Robert Lightfoot announced Feb. 15 that he had asked William Gerstenmaier, associate administrator for NASA’s Human Exploration and Operations Mission Directorate in Washington, to conduct the study, and it is now underway. NASA expects it to be completed in early spring.”