NASA is launching its boldest test flight in decades this week. An unmanned capsule will head off on Thursday to reach a distance of 3,600 miles from Earth—the farthest space mission with a craft designed to accommodate humans since the final Apollo 17 trip to the moon in 1972.
Called Orion, the program will mark a key initial step toward a human mission to Mars. Orion is also designed to excite the public’s imagination for deep-space exploration, much as the Apollo moon missions sparked an interest in space and produced civilian engineering triumphs. With the first test flight on Thursday, NASA wants to make it abundantly clear that much of the hardware that can get humans to Mars already exists and is ready to fly.
“My hope is that when we fly the capsule on Thursday, it will energize the public and energize that middle schooler [who] isn’t quite sure what he wants to do, but he likes math and science,” says Richard Boitnott, an engineer at NASA’s Langley Research Center.
No one is about to strap on a suit and launch to Mars any time soon. Despite NASA’s excitement, the pace of development—driven by Congressional funding—means that the next Orion test flight won’t happen for nearly three years. The first flight with astronauts isn’t planned to take place until six years from now.
The first Orion mission to Mars isn’t anticipated until about 2035, preceded by numerous shorter flights for the four-person capsule to help improve technologies that will protect Mars-bound astronauts from radiation in deep space and the physiological impairments of a zero-gravity environment. One of those flights, set for the mid-to-late 2020s, will involve a rendezvous with an asteroid redirected by a robot spacecraft to orbit the moon. The mission will dock with the robotic spacecraft carrying the asteroid and then collect samples.
On its first flight Thursday, the Orion capsule will orbit earth twice, carrying 1,200 sensors. After a flight of four hours and 24 minutes, Orion will drop into the Pacific Ocean about 600 miles from San Diego, slowed to about 17 miles per hour by large parachutes. The USS Anchorage will collect the capsule.
Lockheed Martin is lead contractor for the project. The first flight is designed primarily to test the craft’s thermal protection—the largest shield system in the history of space flight, according to NASA. The distance is needed to help Orion achieve a speed that could top 20,000 mph to test the thermal shield. As a deep-space capsule designed to return to earth, Orion’s speed will generate reentry temperatures of 4,000 degrees Fahrenheit—much higher than vessels descending from low-earth orbit, such as Russia’s Soyuz capsules or the retired space shuttle fleet. The Apollo missions had to manage reentry heat up to 5,000 degrees; a Mars mission may well test 6,000 degrees.
The first flight will also test Orion’s launch-abort system, a powered crew-escape pod that is certified to work between launch and 300,000 feet. The system, which responds in milliseconds if an emergency is detected, is the most sophisticated NASA has flown to date, according to Kevin Rivers, the manager who oversees the system. “It’s all commanded by the computers. There’s no human in the loop,” he says.
The initial flight will be conducted with a Delta IV rocket built by the United Launch Alliance, a joint venture of Boeing and Lockheed Martin. Future Orion missions will be powered by the Space Launch System, the largest rocket in NASA history. It is scheduled to fly an Orion mission in 2018.