NASA's asteroid mission calls for a robotic spacecraft to grab a boulder from an asteroid and return it to cislunar space.
It seemed like a good idea at the time. Back in 2010 President Obama wanted to distance himself from the space exploration programs of George W. Bush and his predecessors. Humans had been to the Moon, and while they would one day go to Mars, the president reasoned, they needed a more realistic near-term destination. He chose an asteroid.
“By 2025 we expect new spacecraft designed for long journeys to allow us to begin the first-ever crewed missions beyond the Moon into deep space,” Obama said at Florida’s Kennedy Space Center, during the one space policy speech he has given as president. “So we’ll start by sending astronauts to an asteroid for the first time in history.”
An asteroid offered a couple of key benefits. It was new—no human had visited one before. And with a shallow gravity well, it didn’t require expensive landers and ascent vehicles to get onto and off its surface. But there were also problems. Even after searching for a couple of years, scientists couldn’t find a suitable asteroid that came close enough to Earth for astronauts to reach it in a timely manner, and the Orion vehicle NASA was building could only support a crew for 21 days in deep space.