Europe’s ExoMars enters Mars orbit, but lander feared lost
DARMSTADT, Germany — The European Space Agency on Oct. 19 successfully placed its Trace Gas Orbiter satellite into Mars orbit, where it will examine Mars’s atmosphere before changing orbit to become a data relay station for future U.S. and European Mars rover missions.
The orbiter’s Schiaparelli entry, descent and landing payload, which successfully separated from the orbiter on Oct. 16, entered the Mars atmosphere on Oct. 19 and survived long enough to confirm that its heat shied functioned as designed and that its parachute appeared to deploy as expected before being ejected too early.
The data available as of early Oct. 20 was not clear on what happened next. No communications were received. But one target of the investigation was whether the software program running the parachute, which was designed to act as a function of time, positioning and velocity, simply misread the data.
That left the 300-kilogram Schiaparelli package in what may have been 50 seconds of free-fall. Its retro-rockets functioned at least partially for 3-4 seconds after the parachute was ejected, far short of the nominal duration, and at what appeared to be a higher altitude and speed than what was designed.
“The parachute ejection was not exactly according to our expectations. We cannot judge yet under what logic” the lander’s computer gave the order, Andrea Accomazzo, head of ESA’s planetary mission division, said at ESA’s Esoc space operations center here Oct. 20 during a press briefing.
No further data was received about its status from the European orbiter or from NASA’s Mars Reconnaissance Orbiter. The possibility of a crash landing was being examined. ESA officials said they would use the coming days to and and on Oct. 20 ESA officials set themselves the task of stressing that whatever failure occurred on Oct. 19 was outmatched by the successes.
ESA officials said the data harvest, totaling some 600 megabytes, is large enough to provide answers to the remaining questions. But Accomazzo said it would take a few days, and possibly as long as a few weeks, to complete the picture.
Beginning a 6-week spin cycle
In the meantime, ESA officials on Oct. 20 began what may be the complicated task of persuading its member governments that whatever failure occurred on Oct. 19 was outmatched by the successes.
They don’t have much time. ESA government ministers are scheduled to meet Dec. 1-2 in Lucerne, Switzerland, to set a multi-year policy roadmap and to secure funding for the International Space Station and several other programs, including ExoMars 2020.
The orbiter and lander package that arrived in Mars orbit on Oct. 19 is the first of two missions that comprise ESA’s ExoMars program. Both are bilateral efforts with the Russian space agency, Roscosmos, which provided the launch of the 2016 mission and is expected to provide the same service, plus a lander package, for the 2020 mission that is supposed to carry a European rover vehicle.
ESA and Roscosmos earlier this year had scrapped a planned 2018 launch of the Russian lander and European rover because multiple elements in Russia and Europe.
ExoMars’s unusually complicated funding history left it about 200 million euros ($220 million) short of the 1.2 billion euros estimated as necessary for ESA’s share of the mission.
The decision to delay the 2018 launch by two years added another 100 million euros to the amount due.
ESA Director-General Jan Woerner, former head of the German space agency, DLR — Germany is not a major ExoMars contributor — in the past has been highly critical of ExoMars’ budget and schedule issues. But in recent weeks Woerner has spoken as if the 2020 mission was already approved.
During the Oct. 20 press briefing, Woerner accented the positives on the Oct. 19 events. He said the Schiaparelli package, whose battery power is estimated to last no more than 10 days or so, was always considered an experiment and that it should be judged as a success.
Update: On Oct. 21, Woerner presented the math on the overall mission. The orbiter, he said, was 80 percent of the total mission’s value and is a 100 percent success. The lander represented the remaining 20 percent of the mission’s value. Given how much data was received during its descent, the lander should be viewed as an 80 percent success. Total mission report card: a 96 percent success.
Hoping to avoid the Beagle 2 syndrome
Whether that view is shared in Italy remained to be proved. ESA officials agreed before Oct. 19 that the orbiter’s mission was far more important than the Schiaparelli payload from a scientific point of view. But one ESA official said the political importance of Schiaparelli, especially in Italy, ExoMars’s biggest national contributor, should not be underestimated.
The Russian side of the equation is even more difficult to estimate. Roscosmos officials have insisted that the 2020 mission has been protected from the budget cuts at the agency.
But a Roscosmos statement on Oct. 19 on ExoMars that cheered the success of the Trace Gas Orbiter made no mention of the 2020 mission.
ESA and other officials here the evening of Oct. 19 said the concern is that the public perception of the 2016 mission will overplay the possible loss of the lander.
In December 2003, ESA successfully placed the Mars Express orbiter into Mars orbit, where it remains healthy and has produced spectacular images for 13 years. But Mars Express also carried a small, low-budget lander called Beagle 2, which failed to survive the Mars landing but did land intact.
For days after the Christmas 2003 event, the European and global press fixated on the lost little Beagle 2 and all but ignored Mars Express.