Christmas on MarsAccessible controllers, inaccessible spacecraftGradually it emerged how precisely the target orbit had been hit: at 8:20 CET Flight Operations Director Alan Smith could already tell me in private, based on ongoing Doppler measurements, that the deviation was less than half a percent. The opportunity to talk to leading flight controllers during the actual operations was something that set ESA’s “Christmas on Mars” event apart from earlier similar events I had experienced at NASA (and it had taken public affairs officers some effort to make it happen, I was told): the immediacy of the events near distant Mars was heightened enormously. Except for one aspect of course: no one could tell us about the state of the British lander, Beagle 2, that had been on its own and asleep since separation from Mars Express six days ago—because nobody in the Universe had any knowledge about is fate. When NASA had lost its Mars Polar Lander in 1999 and had then only found out by pure chance and months later about the tragic software glitch that most likely had killed it, the decision was made to never land on a planet again without constant communication of some kind. To fail is okay, the thinking went, but to learn from failures and to do better the next time, you must know what went wrong. Even the comparably simple Mars Pathfinder had been sending out faint but telling “semaphores”, tone signals that announced its (perfect) status during descent and after landing, and the Mars Exploration Rovers will be transmitting similar signals to Earth—and even much more detailed telemetry to Mars Odyssey—during their descent. But Beagle 2 did not have such a feature and ESA hadn’t insisted on it being added as a condition for taking the British hitchhiker along for the ride.
ESA’s managers had been more concerned about scores of other Beagle safety aspects that directly affected the orbiter, and they had to force many modifications upon the British designers (which they duly accepted). Continuous telemetry during entry and descent would have been a nice feature but it was not essential for the success of this particular mission—though hugely helpful for eventual follow-up projects, in case of a fatal outcome—and thus it was not required. The whole project, both highly innovative and horribly underfunded, had been on the verge of collapse frequently ever since its proposal in 1997, ESA’s Science Director David Southwood told me, and one more demanding requirement could easily have been one too much. But now ESA’s managers surely must have had second thoughts about their decision as Beagle 2 had already missed its first tentative opportunity to phone home. The landing should have taken place at basically the same time when Mars Express began its insertion burn, and the targeting of the inert probe had been so precise when it was jettisoned that there is no question whatsoever that Beagle 2 is on the surface of Mars. The error ellipse of the landing zone is even much smaller now than it was before, just 31 x 5 kilometers wide. But when Mars Odyssey first passed over that region, no signals whatsoever were received at this orbiter’s mission control at JPL: It was Southwood himself who broke these sobering news at 7:34 CET—not without adding that many more opportunities for contact would follow and that one should not worry too much. Indeed numerous celebratory speeches followed in the next half hour, in which the German minister for research declared that “this mission is a success already now” and a beaming Director General of ESA thanked everyone involved “for this beautiful day.” More hours passed now, with speculation voiced by Mike McKay on ESA’s own TV channel about all those glitches that may have prevented Beagle from reaching Odyssey during the first attempt. There could be many reasons, from a tilted lander to the wrong temperature of the transmitter. In the coming days there would be numerous possibilities to try to hail Beagle with Odyssey again, often under more favorable geometry. The large British radio telescope at Jodrell Bank would also try to catch the lander’s transmissions several times, and another radio telescope at Stanford University was also going to help. From ESA’s point of view Beagle had always been an addendum to the primary spacecraft anyway, and the Director of Technical and Operational Support, Gaele Winters, could thus state the obvious: “We have a running mission,” at least with the orbiter.
As the next opportunity to contact Beagle would only come in another 15 hours, the only milestone left in the 10-hour vigil at ESOC was the resumption of full Mars Express telemetry in X-band through the high-gain antenna. This time we could actually watch a spectrum analyzer: the appearance of two strong spikes at just the predicted time at 9:49 CET (3:49 am EST December 25) made obvious how healthy the spacecraft was. McKay read the first bits of housekeeping data that arrived now in real time to the somewhat dazed but wildly elated audience (the Beagle team members were at a different all-night vigil in the U.K.). There were only minor anomalies it seemed, and Mars Express was in a “very good condition.” With that the minister for research climbed the stage once more, there was champagne for all and even some presents like a “Europe on Mars” scarf given out by ESA staff: This was Christmas morning, after all. Epilogue: As could have been feared, the uneasiness about Beagle 2 would largely overshadow the total success of Mars Express in Europe’s mass media, with very few exceptions. When the final orbit is reached after some maneuvers by January 4th and the first test data from orbit become available—e.g. from the sophisticated High Resolution Stereo Camera —by mid-month this impression will hopefully change. By then the fate of Beagle 2 should also be clear after dedicated contact attempts by Mars Express and its lander-specific telecom equipment. Until these efforts are exhausted, the lander portion of the mission—so close to the heart of much of the public—will not be declared a failure, Southwood has assured me in no uncertain terms. Home |
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