Spirit -- NASA's first Mars Exploration Rover -- survived the ‘six minutes of terror' entering and descending through the atmosphere to land safely -- and upright -- in Gusev Crater on the Red Planet. Just two hours after the confirmation signal of the landing, the first engineering data and images began streaming into the MER Mission Control at the Jet Propulsion Laboratory (JPL), where Spirit and her twin, Opportunity were built.
The images are so clear, crisp, and telling that even the MER Mission Control team members were staring wide-eyed and open-jawed at their monitors. Gusev Crater -- which many Mars scientists believe was once a large lake -- was considered somewhat risky as a landing place because of the potential for large gusts of wind that could have threatened the survival of Spirit.
When the first true confirmation signal finally came in around 8:51 p.m., about 16 minutes later than expected, the MER team broke out in cheers and shouts, as NASA Administrator Sean O'Keefe, who flew in for the big event, congratulated the team. Hugs and hand- shakes went all around. And, there were even cheers and claps from the makeshift newsroom set in Von Karman Auditorium on the NASA center's 'campus.'
"Well, we did it!" exclaimed JPL Director Charles Elachi, showing the thumbs-up sign.
The rover entered the Martian atmosphere right on time at 8:29 p.m. , Pacific Standard Time (PST), traveling at 12,175 miles per hour, 25 times the speed of sound. It began decelerating as expected, and at 25,000 feet, 446 miles per hour, the parachute deployed near the expected time.
When the report came that Spirit was bouncing on Mars, most members of the MER team in mission control jumped from their seats and began to cheer. A momentary signal was picked up. Then it was gone, and the expected confirmation tones were longer in coming than initially hoped, providing for some very tense and confused moments.
In fact, there were a few long moments of absolute silence in both Mission Control, as well as the 'newsroom' as everyone awaited for Spirit to stop – and survive the bouncing – and return the tones. That signal finally arrived, indicating that Spirit had arrived and was communicating. And, in the back stages of JPL, the bottles of champagne were pulled out -- or was it really apple cider?
Meanwhile, back at The Planetary Society's Wild About Mars event, the cheers, tears and shouts of joy rippled through a crowd that had now grown to more than 2000 people. Ones by twos by fours, they had been steadily streaming into the Pasadena Center since 5 p.m., to watch the landing in real time on a giant screen and share in the experience.
The event was replete with celebrities the likes of beloved Martian Chronicles author Ray Bradbury, an advisor to The Planetary Society, and the Lord of the Rings' John Rhys Davies, who cheered the exploration on. And one person there really knew how the Spirit team felt. Donna Shirley -- the Planetary Society Adviser who had been hosting the event's 'guided tour,' explaining step-by-step what was happening and what the delays meant, is the mother of Spirit and Opportunity's predecessor -- Sojourner . She lived the experience back in 1997.
At a news briefing later at JPL, Administrator O'Keefe, director Elachi, and MER team members addressed the assembled throng of reporters: "Tonight represents the very best of what NASA can achieve -- this is a remarkable team," O'Keefe began.
"You have no idea how this feels," sighed MER Project Manager Pete Theisinger. "I said when I woke up yesterday that when I woke up Sunday, the world would be different -- and it truly is."
The team was still marveling about just how well it all went, despite the few minutes of wondering. "Everything happened the way we expected it to happen," exclaimed JPL's Rob Manning, the rover entry, descent, and landing development manager.
The fact that Spirit is "alive" on the surface, Theisinger pointed out, "is a very good harbinger of things to come. How right he was.
Spirit, meanwhile, began executing a programmed series of actions, including retracting its airbags, opening the lander petals, unfolding the rover's solar panels, and erecting its camera mast.
Then, around 10:49 p.m., the Mars Odyssey orbiter flew over the landing site, and Spirit beamed up data with its UHF antenna. At 11:31 p.m., those first data returns starting coming in. The first images followed 2 minutes later. They were, simply, remarkable. The black and white images revealed everything from a snapshot of the final descent to images of the Martian landscape and the lander/rover itself. One mosaic image revealed that the lander had rolled to a stop near an awfully big rock. They also clearly showed that all the programmed commands had been carried out -- the airbags were retracted, the camera mast had raised, etc.
"Thank you, thank you!" Steve Squyres, principal investigator of the science package aboard Spirit, said extending his hand to Manning in the Mission Control room. A couple of weeks ago, Squyres told The Planetary Society he was trying to catch up on his sleep -- just in case. Well--? "I'm not sleeping tonight!" he declared joyfully later.
There were at least a few serious moments, especially in considering Opportunity's scheduled arrival in three weeks and any new-found lessons that may help Spirit's twin to a safe, sound landing. "We are not going to assume that because this one was successful that Opportunity will go the same way," noted Elachi. The second Mars Exploration Rover is slated to land in Meridiani Planum on January 24.
But tonight was a big deal -- and a night for celebrating success. Spirit's arrival on Mars is clearly an achievement for the beleaguered space agency and, perhaps, for other elements of society. "Hopefully, we have inspired people," mused Richard Cook, the MER deputy project manager.
"I was here when we landed on the Moon, and we all went outside and looked into the sky," recalled Elachi. "Well, tonight you can go outside and look up and see Mars, where we just landed!"
After returning its first assault of shock and awe in pictures, Spirit went to sleep, but was slated to wake up Sunday morning, January 4, when Mars Global Surveyor (MGS) flies over Gusev Crater at 7:25 a.m. PST, providing a span of about 15 minutes during which the rover can send more data to the orbiter, again via UHF transmission. NASA's Deep Space Network (DSN) antennas here on Earth will be listening for MGS' relay of that information between 7:51 a.m. and 8:02 a.m. Odyssey will make a return flight over the landing site at Gusev for another opportunity to receive data from Spirit at 11:30 a.m. Then Spirit will 'hit the sack' for awhile more.
In the early morning hours, congratulations arrived from overseas. At a press briefing in London, Colin Pillinger, the Beagle 2 lead scientist, and Mark Sims Beagle's mission manager, congratulated their colleagues at JPL on the successful landing.