An unmanned Orion capsule will make two orbits around Earth, going into deep space -- far beyond the lower orbit of the International Space Station -- before splashing down in the Pacific Ocean, officials said.
Orion's orbit is expected to peak at nearly 3,700 miles above Earth, the farthest any NASA spacecraft built for humans has gone since the early 1970s.
That distance is "significantly higher than human spaceflight has gone since Apollo," Larry Price, Orion deputy program manager at capsule manufacturer Lockheed Martin, told the Orlando (Fla.) Sentinel. "The reason for that is so we can get a high-energy entry so we can stress the heat shield."
That's vital if a human flight, set for 2021, is to survive the brutal re-entry into Earth's atmosphere where temperatures are expected to reach 4,000 degrees.
"The beauty about flying in 2014 is that we can learn early [if there are problems], so if we find something we've really got to fix we've got time before we fly people," Mark Geyer, head of the Orion program at NASA, said.
The capsule project was salvaged from the defunct Constellation moon program, which President Obama and Congress canceled in 2010.