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Mars Pathfinder Launchby Donna Shirley
December 6, 1996
Another perfect launch for the Mars missions! We are now two for two thanks to the wonderful Delta rocket built by the McDonnell Douglas Corporation of Huntington Beach, California. The Kennedy Space Center launch facility crew and the Goddard Space Flight Center Office of Launch Systems who procure the Delta also were super.
The launch happened on the third opportunity, December 4, at 1:58 a.m. EST. The launch period actually opened on December 2, but the weather was so bad that they decided at 8 a.m. to cancel the attempt for that day. On December 3 many of us went out to the launch pad to watch the gantry roll back. This was supposed to happen at 5 p.m. but didn't actually occur until 7:30 p.m. It got colder and colder, and there was a prelaunch party scheduled. Gradually, people trickled away to the party. A few diehards, including me, Howard Eisen of the rover team, Tom Shaw of the Pathfinder team, and Dave Murrow of the Mars Surveyor 98 team, were all that were left to see the rocket standing free of the supporting structure. It was worth waiting for, shining in the spotlights, gleaming blue and white. Later that night, out at the launch control center, I was sitting at a console with Wes Huntress, head of NASA science; Wes's deputy, Earl Huckins; Ed Stone, the JPL director; and the Director of the Kennedy Space Center. At the consoles you can hear all the cross talk of the launch vehicle people, the spacecraft people, the weather people, and the range managers. They have big-screen t.v. displays in the front of the room so you can see the vehicle, the weather data, the spacecraft team, and other views.
Everything was counting down to a 2:03 a.m. launch. But it wasn't our day. First, the winds aloft looked bad. The range sent up balloon after balloon to see what the winds were like, and gradually they began to improve. By the fourth balloon they looked acceptable and we all began to get excited. But there was another problem. One of the ground computers that keeps track of the telemetry from the propulsion system on the launch vehicle kept having problems. After much discussion the launch vehicle team decided to change to a backup computer. But about 2 minutes before the launch time, that computer had trouble also, and the launch was scrubbed.
Everyone sagged. We'd been running on adrenaline, not a bit sleepy, but once there was no launch everyone who could went home to bed. The poor launch team had to shut down the vehicle safely and get ready for tomorrow.
Just after I got to bed at 3 a.m. I got a call from the "Today" show saying they still wanted to have me live on their show at 7 a.m. the next day. Then, they called again at 6 a.m. saying, "No, we'd rather have you on the morning after a successful launch." Grrrrrr. I finally got back to sleep, only to get a call at 10 a.m. from some people in Washington D.C. who needed some information. After that, I had lunch, did some work, then took a nap until about 10 p.m. and went back out to the launch control room.
This time everything was going smoothly. The wind was light, the weather was clear, and they had fixed the balky ground computer. Everything ticked down. This time I watched the displays until about 30 seconds to launch, then ran outside with Wes, Earl and Ed to see the launch.
There was a building between us and the launch pad, but suddenly the sky lit up like sunrise. "There she goes!" yelled someone, and within a couple of seconds the fireball rose over the building and streaked through the sky. The roar of the rocket shook us a couple of seconds later. The rocket formed a giant arc through the sky, heading for a fat crescent moon hanging above us like the Cheshire cat's grin. Mars was a red dot above and to the left of the moon. The Delta's six solid rocket motors dropped off and twirled glowing through the sky like fireworks. Then the rocket slid past the edge of the moon (from our perspective) and disappeared.
I went back and watched the events tick off the schedule. MECO (Main engine cut-off), Second engine start, SECO, acquisition by the tracking stations. Everything was perfect.
I went over to the SAEF-2 building where the JPL spacecraft launch team was waiting for contact with the spacecraft, an event scheduled for an hour and a half after launch. The team was all wearing identical Pathfinder t-shirts and sitting in front of consoles with their headsets on. Everything was quiet because there was nothing the team could do until the spacecraft separated from the launch vehicle and had its radio signal acquired by the Deep Space Network.
We waited. We watched the screens. Guy Beutelschies, the Pathfinder test conductor, was relaying messages from the launch control site. Acquisition of launch vehicle telemetry by the ARIA aircraft which relay telemetry when the ground stations can't see the vehicle. Third Stage firing and cutoff. Shroud deployment. And finally, spacecraft separation. Pathfinder was on its own.
Silence. Then a single number changed on the list of spacecraft telemetry parameters on the consoles. "We have a packet," shouted Guy. That meant that the spacecraft was talking to the Deep Space Network. Still, everyone waited. Suddenly, a lot of numbers changed! "We've acquired the spacecraft!" Then there were cheers from the whole spacecraft team. They had done it!
After celebrating for awhile with the team, I went out to the Kennedy Space Center press site, where Tony Spear (the Pathfinder project manager) and I were on a panel talking to the few diehard reporters still up at 4:30 a.m. By 5 a.m. I was sitting in the press room giving an interview to a newspaper reporter. After a great breakfast in the Kennedy cafeteria, with a lot of sleepy cameramen and public information people, I did a live interview for the "Today" show on NBC. They wanted it outside with the huge Vehicle Assembly Building in the background. (A "signature shot," they said). I shivered through a 5-minute interview in the chilly dawn wind. It turned out I was competing with myself because I was also on a tape run by "Good Morning America" on ABC! That evening, there was a long piece on the Pathfinder mission on the "Jim Lehrer News Hour" on PBS. And Pathfinder got lots of other press coverage. The best picture was one by Reuters which was a time-lapse picture of the arc of the rocket streaking from the launch pad past the moon. We're on our way. Wish us luck.