That landing is scheduled for 1:31 a.m., and officials said they could know almost immediately if the rover was safely on the ground. That tracking would come from the Odyssey orbiter circling Mars, if the spacecraft is able to get to the right location at the right time.
If not, the waiting time for a final answer on whether the rover was safely on the surface could range from two to eight hours. If no signal arrives from Curiosity via three Mars orbiters and the Deep Space Network after 18 hours, NASA officials said, then they would start to worry about its safety.
The final descent has been pre-programmed and the army of engineers and scientists at the Jet Propulsion Lab’s Mission Control have no control over it. “Our position will be identical to anyone at home,” said Adam Steltzner, lead of the Entry, Descent and Landing (EDL) team. “We’re all along for the ride.”
Speaking for the team as a whole, Steltzner said they were “Rationally confident, emotionally terrified and ready for EDL.”
Because the rover is so much larger, more complicated and more ambitious than earlier models, it has to land in a new and far more hazardous way. The landing, which could never be tested in full on Earth, includes a hovering rocket stage, a kind of sky crane, to lower it to the ground. NASA’s chief scientist John Grunsfeld has said that because of that heightened landing difficulty, in addition to the unprecedented sophistication of the instruments on board, Curiosity is “the most important NASA mission of the decade.”
The Curiosity landing is shaping up to be an international spectacle. Formal “landing” parties have been scheduled from South Australia to Rome, from Israel to Crete; and in the United States from Atlanta to Seattle, Milwaukee to Honolulu.
NASA also has helped organize a landing gathering in New York’s Times Square, which will feature a large screen that will beam the streaming news from atop a building and high above the crowd.
Reaching, orbiting and landing on Mars is notoriously hard. In addition to the European Space Agency, nations including the United States, the former Soviet Union, Russia, the European Space Agency, China and Japan have sent missions to Mars since the late 1960s, but only about one-third of them have succeeded.
The United States is the only nation to land a vehicle on Mars and complete its mission, having done it six out of seven tries.