Mission controllers have yet to receive a signal from the European Space Agency’s (ESA) Schiaparelli lander, a smart car–size spacecraft that attempted to touchdown on Mars on Wednesday.
“Absence of information is the worst thing you can have, because there’s nothing you can do about it,” says Andrea Accomazzo, an ESA project scientist speaking at a news conference in Darmstadt, Germany. “It’s true that the data we have collected so far is not exactly nominal for Schiaparelli.”
Schiaparelli’s mother ship, the Trace Gas Orbiter (TGO), successfully entered Martian orbit around the same time the lander began its descent, to begin a mission searching for signs of geologic or even biological activity in Mars’s atmosphere. Together the lander and orbiter are part of the joint European-Russian ExoMars program.
At first the entry and descent appeared to be going well for Schiaparelli, which is named for the 19th-century Italian astronomer Giovanni Schiaparelli. Designed to demonstrate technology for depositing large payloads on Mars, the lander first would use a heat shield to bleed off the bulk of its 21,000 kilometers-per-hour entry speed as friction against the thin Martian air. Next it would deploy a parachute, followed by a radar-guided, rocket-controlled descent and a final two-meter free fall to the surface where impact would be cushioned by Schiaparelli’s crushable, cushionlike underside. It would land within Meridiani Planum, an equatorial region on the same side of Mars that hosts NASA’s Opportunity rover. All the while it would send out a simple, diagnostic radio tone so its progress could be monitored.
On Earth, listening stations picked up the signal and tracked Schiaparelli’s descent to Mars—even seeing a fluctuation likely due to the lander’s successful deployment of its parachutes. But a minute before it was set to reach the surface, when it was supposed to still be hundreds of meters above Mars, Schiaparelli’s radio signal abruptly fell silent. ESA’s Mars Express spacecraft orbiting overhead was also watching Schiaparelli’s radio signal, but a preliminary analysis of those observations has proved inconclusive beyond revealing the same sudden loss of signal. “We can’t conclude the real status of [Schiaparelli] at the moment, but indeed it did enter the atmosphere and operate mostly [as expected],” said Don McCoy, ESA’s ExoMars project manager, speaking at the press conference.
Jan Woerner, ESA’s director general, tried to stay optimistic during his remarks, encouraging his audience to “Cross your fingers. I hope that we get a positive message very soon. … The day is not over, and Mars is still there.”
Soon, however, the optimism began to fade. Two hours after its scheduled landing, Schiaparelli was scheduled to establish two-way communication with NASA’s Mars Reconnaissance Orbiter as the satellite passed over the planned touchdown site. But at a second, subsequent news conference ESA officials made no mention of this event.
Faced with what appear to be multiple failed attempts to detect or communicate with Schiaparelli, ESA officials are now contemplating the worst. Schiaparelli certainly landed on Mars but may not have survived to tell the tale. If it crashed it would join a long, distinguished list of previous failures—to date, more than half of the landing attempts on Mars have ended in catastrophe.
More certainty about the lander’s fate—and a diagnosis of what went wrong—will not come until the ExoMars team has analyzed detailed telemetry data on Schiaparelli’s descent, as recorded and transmitted by its mother ship, TGO. Those results are expected on October 20. Additional information could come from NASA’s Opportunity rover, which attempted to photograph the lander as it deployed its parachute during the descent, but those images were not guaranteed—and if taken, they have yet to be transmitted to Earth.
Even if Schiaparelli did survive the landing, the mission’s time is already running out. Because it was chiefly meant to demonstrate landing technology rather than perform science on the surface, the lander runs solely on chemical batteries that only contain a few days’ worth of power. This would have been enough to operate Schiaparelli’s small suite of instruments to study Mars’s dust storms, atmosphere and electromagnetic field, but not much else.
For now, the ExoMars team still has much to celebrate. TGO’s successful entry into Mars’s orbit is a major achievement that will not only open a new window on the planet’s atmosphere but also will shore up the dwindling orbital infrastructure there by acting as a vital communications link for current and future surface missions. One of those future missions will come from the ExoMars project itself, which intends to land a rover in 2021. Whether Schiaparelli’s potential failure could alter or delay those plans remains to be seen.