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A Spirit of Opportunity Successful rover landing sets the stage for a new era in Martian exploration by Michelle Evans
“Longest ten minutes of my life!”
This comment from OCSS member Mike Cutler sums it up best for what we all were feeling as we waiting tensely for word to come from Mars that the Mars Exploration Rover (MER) Spirit arrived safely.
Time: 8:29 pm PST, Saturday, January 3. Around the globe, people were watching and listening as MER-A slammed into the atmosphere of Mars at over 12,000 mph. In just six minutes, if all went well, the first rover since Pathfinder in 1997 would arrive and prepare for three months of operations across the flat terrain of Gusev crater.
Unlike the last attempt to land on Mars with the Mars Polar Lander (MPL) in 1999, MER was equipped with telemetry that operated all the way to the surface. If anything went wrong, there would at least be a way to decipher what happened. The telemetry was simple: a series of tones that occurred when specific events happened on the spacecraft. Atmospheric entry, deceleration within limits, supersonic parachute deployment, heat shield jettison, air bag deployment, back shell rockets firing, bridle cut, hit the surface and bounce.
It was now 8:35 pm. What a way to come to Mars!
Everything appeared fine, but then, after the first bounce, it seemed that the signal was lost. It takes that “longest ten minutes” to reacquire the signal and verify that everything happened as advertised. At the Jet Propulsion Laboratory (JPL) and Planetfest in Pasadena, thousands of scientists, engineers, and the general public, all erupted into cheers and shouts. Across the country and around the world, everyone watching shared a similar reaction. A human emissary had returned safely to Mars.
“We think this accomplishment approaches that of landing men on the Moon in terms of complexity, but I don’t believe the public at large has that impression,” said Phil and Susan Mackey. “Our collective hats go off to all the men and women who made this possible.”
As Mary Doney succinctly stated, “It was exciting to see the Mars Exploration Rover land perfectly.”
Throughout the build-up to the landing, the project personnel at JPL had tried to downplay expectations to the public. It might take a while to find the telemetry. Even if all goes well, the first photographs may take a day or more to be transmitted. However, Spirit performed better than anyone’s expectations.
“We got home, put the kids to bed, and saw the pictures from Mars before midnight on the news,” said Susan and Arthur Kienle. “We wanted to leave the kids with the grand-parents so we could stay longer [at Planetfest], but we always include them in space functions because it is important. Space is not only our future but for future generations. Ray Bradbury’s comments hit home for me. He was asked, ‘Why go to Mars?’ Bradbury responded, ‘Why? Because it is the future!’ Not only are we space enthusiasts, we want to pass it on to our kids.”
Beyond just thinking about the future, what is the purpose behind NASA sending rovers to Mars? Dr. Edward Weiler, Associate Administrator for Space Science at NASA in Washington, D.C. stated, “The bottom line is that our whole program is geared toward the long term goal, not to answer the geology question or the science question, but to answer the human question: Are we the only things in this universe? That’s why we’re here today. It’s a continuation of that process. It’s not just about rocks. It’s not just about minerals. It’s not just about pretty pictures. We’re taking another step in the human quest to find out if we’re alone.”
Each Mars rover carries nine cameras. This is more than has been carried on all the spacecraft that have previously made it to the surface of Mars combined. And each of these cameras provides higher resolution than any of those previous cameras. Also aboard is a robotic arm that will be used to sample the surface for analysis and transmission back to Earth. At the end of the arm is a RAT. No, this is not the first rodent on Mars, it is the Rock Abrasion Tool, which serves as the robotic equivalent of a geologist’s hammer. When a target is identified, RAT moves in and grinds away to create a clean surface for examination. Then the Microscopic Imager comes into play, peering at the surface to look for signs that life may have once existed on Mars. The imager is capable of resolution similar to that obtained here on Earth, such as when a Martian meteorite was examined several years ago and found to have possible remnants of life.
Getting to Mars can be hazardous. Yet, it appears that the public always anticipates and requires 100 percent success. This is not always the case. Mars has often been termed a graveyard for spacecraft from Earth. About 50 percent of the vehicles that traverse the void to the red planet are never heard from again. Just a little over a week prior to Spirit’s arrival, the European Space Agency found out first hand how the odds work. A two-part spacecraft, an orbiter and a lander, were slated to enter the influence of Mars on Christmas Eve. The lander, dubbed Beagle 2 after Charles Darwin’s famous ship, was last seen in a photograph snapped by the orbiter as the lander separated and drifted away into the darkness. Not having learned the same hard lessons we did in 1999 with the loss of MPL, Beagle 2 carried no telemetry as it entered the atmosphere (see O.C.Space, March 2000: “Mars, Where Do We Stand”).
Dr Weiler explained, “It still is a tough place, an unpredictable place. If you look at the Pasadena forecast from three days ago, it was supposed to be raining today, and yet we’re trying to predict the winds 200 million miles away.”
As of the writing of this article, it is unknown if Spirit’s twin rover, MER-B, Opportunity, will make it safely to the surface, halfway around the planet at Meridiani Planum. By the time you read this, that information will be known and, hopefully, it will be good news. If so, this will be the first time since 1976 that two spacecraft will be operating simultaneously on the surface of Mars (Viking 1 and 2).
Dr. Charles Elachi is the Director of JPL. When asked if luck would have anything to do with the success of the MER missions, he told us, “I don’t mind luck because I know that luck comes to the people who work hard for it. And I think that the people here have all worked very hard for it. If that gives us extra luck, that’s fine.”
One interesting thing about these missions is that the teams operating the rovers will be timeshifting to keep pace with the Martian day. Each “Sol,” as they are called, is about 40 minutes longer than the day on Earth. Over the course of the nominal three month mission, the teams will have to timeshift approximately 60 hours. I asked if the managers and directors will shift their schedules to keep pace with the teams.
Dr. Weiler told me, “I wish I could stay here instead of going back to Washington, and do just that!”
Dr. Firouz Naderi, JPL Mars Program Manager explained, “A lot of the work is going to be done by the scientists, who receive the data, interpret the data, and work with the engineering team to send the commands for the next day. We have over a hundred scientists who have left their homes around the country and they are now located here in Pasadena. They are broken up both by instrument and by discipline. So we have adequately staffed, both from the engineers and the scientists, to man the missions around the clock.”
Even Dr. Elachi plans to stop by. “I intend to, every once in a while, come in at midnight to visit the team, just to keep their spirits up. We had people working here on Christmas Day, so my wife made them cookies and I brought them in to thank them.” Science and exploration are always about finding out what is over the next horizon. Both Spirit and Opportunity may help us attain those goals for the first time on Mars. Dr. Weiler said, “Scientists will come back and say, give us one more rock. But at that point, the thinking is that, if we complete the science program and there’s juice left in those batteries, I would like to put the pedal to the metal and and send those rovers over the next hill to do some real exploring. That’s exploration. If you want to get the kids excited in this country, and there’s a hill or a valley in the distance, I’d like to let those rovers go and go as far as they can.”
What does the future hold for Mars? With the new space policy outlined by President Bush (see page 3), these robotic missions are now serving as a direct connection to future human expeditions. As our member Robert Lanktree told me, “I still say men could have been there by now, in one mission accomplishing all that has been done by robots. I don’t think a manned mission would have suffered the mistakes the robotic ones have; they are more thorough. I know sending humans that far has its problems, but we just need to figure a way through that and get on with it.” XXXX |
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