PARIS — Backers of four European space science missions on Jan. 21 made last-ditch oral presentations in defense of their projects in an attempt to sway the opinion of a jury of space scientists that will select only one of them in mid-February.
The winner will receive development funding likely to approach $1 billion for a mission that will launch between 2022 and 2024. The others will be cast back into the large pool of missions that will be either abandoned or forced to wait another three or four years for their next chance at selection.
A fifth mission, an ambitious attempt to test Einstein’s Equivalence Principle called STE-Quest, had been among the remaining candidates until a late-2013 analysis by the 20-nation European Space Agency that found its technology too risky to be ready for the planned launch date.
STE-Quest managers were permitted to make a presentation here Jan. 21 even though the mission will not be up for consideration by the two European panels to select a winner.
Europe’s Space Science Advisory Committee is expected to make a recommendation to the Science Program Committee in time for the latter body to decide the winning candidate at its Feb. 19-20 meeting.
Having experienced past missions whose technical development ran up against issues well after getting underway, or whose financial requirements swelled beyond the budget, ESA now analyzes the finalists for technical maturity and financial credibility.
The current competitors are bidding for selection as the third Medium-class ESA science mission, for which ESA has set a budget ceiling of about 600 million euros ($800 million). Added to this is the estimated cost to national space agencies in Europe for building the mission’s scientific instruments.
For some missions, the non-ESA contributions by individual nations can total some 50 percent of the entire cost. To avoid a scenario in which one or more nations say they cannot fund the promised development, ESA now has formal sit-down sessions with the respective laboratories to be sure everyone agrees on the extent of the work, said Frederic Safa, head of ESA’s future missions office.
ESA issued requests for proposals for its so-called M3 mission in mid-2010 and received 47 responses. Four finalists, including STE-Quest, emerged. A fifth — the Plato mission to investigate Earth-like planets around bright stars — was subsequently added. Plato had been passed over in the selection of the M1 and M2 missions.
The packed auditorium here was filled with all five missions’ defenders, plus members of the committees that will render judgment.
Advocates for each mission made their case and then answered questions. An illustration of the competitive flavor was given when, during questions following the MarcoPolo-R asteroid sample-return mission presentation, representatives from NASA and the Japanese space agency, JAXA, rose to say their agencies were supportive of MarcoPolo-R and planned to make contributions.
The NASA and JAXA comments were greeted with incredulous laughter and some jeering, presumably by backers of the other missions objecting to any indication that U.S. and Japanese support should tip the jurors’ opinions in favor of MarcoPolo-R.
In the past, ESA has allowed missions that require U.S., Japanese, Russian or other support to be considered for ESA funding. That is no longer the case. ESA officials said that while non-European contributions were welcome, contenders must be able to conduct the full mission program using European funding.
ESA’s Safa had said all four finalists had been cleared for financial, schedule and technical credibility and that while challenges remained, all four should be judged only on their scientific merits. All carried about the same price tags within the allocated budget, Safa said.
Each mission design had been sent to two competing industrial teams to come up with a satellite structure — and initial cost assessments.
All four missions would be launched on Europeanized Russian Soyuz rockets from Europe’s Guiana Space Center in South America.
Only one of the missions, the Echo exoplanet probe to search for planets whose atmospheres may support life, relies on non-European technology for a key element.
The Echo spacecraft would employ mercury cadmium telluride detectors supplied by Teledyne Imaging Sensors of Camarillo, Calif., and mid-wave infrared detectors from the same company.
ESA had already approved the use of Teledyne detectors on its Euclid science satellite, now in development, and has determined that the export of this hardware will not be a problem. The mercury cadmium telluride technology is also the subject of a development program in Europe that may provide results in time for Echo, should that concept be selected, but in any event this should not be considered a risk factor for the mission, Safa said.
In addition to STE-Quest, MarcoPolo-R, Plato and Echo, the other mission competing for M3 funding is the Loft X-ray telescope to observe neutron stars and black holes.
Follow Peter B. de Selding: @pbdes