Crew Dragon to Land in the Atlantic. Watch Live Stream

The hatch has closed, and the SpaceX Crew Dragon is ready to return home to Earth. The capsule is scheduled to make a splashdown in the Atlantic Ocean at around 10:45 a.m. EST. The last step of the mission is the biggest challenge that will determine whether the mission is successful

During descent, Crew Dragon must demonstrate that its novel shape and parachute system will zoom through Earth’s atmosphere undamaged while keeping the cargo safe. The landing technique is similar to that of the Dragon, SpaceX’s cargo carrier, which deploys parachutes to touch down in the Pacific Ocean. However, because the Crew Dragon’s shape is more asymmetrical than that of the Dragon – due to the fact that it has an emergency abort system – there could be some instability during its flight through the atmosphere.

The abort system consists of eight thrusters, SuperDracos, that ignite and propel the capsule to safety in case there are malfunctions during the launch. The resulting asymmetry is what worries SpaceX CEO Elon Musk the most. “I say hypersonic re-entry is probably my biggest concern,” he said during a press conference on Saturday. He did add that rolling during re-entry is unlikely based on the simulations SpaceX has run.

However, astronauts have not returned to Earth in this manner since the 1970s. When the Space Shuttle began its missions in the 1980s, astronauts returned to solid ground. For this reason, NASA is still in the midst of assessing the SpaceX reentry system for human spaceflight. “We’re looking at the physical parameters of how the chutes operate and if we covered all the corners of the envelope and testing,” said Bill Gerstenmaier, NASA’s associate administrator for human exploration, at a press conference before the launch.

After the splashdown, a recovery ship will locate the spacecraft, lift it out of the water and transport it to land. The capsules undocking began at 2:31 a.m. EST, and the coverage of the landing begins at 7:00 a.m. EST.