ExoMars: Schiaparelli does not answer

There is still uncertainty about the fate of the first European Marslander

While the ExoMars orbital probe has successfully penetrated into Mars orbit, the signal from the Schiaparelli state probe has so far failed to materialize. © ESA
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Failure probably: So far there is no contact with the European regional probe Schiaparelli. It is therefore doubtful whether the module has managed to land on Mars. The ESA still tries to receive the signal of the lander with the help of different space probes in Mars orbit. But they no longer rule out a crash landing. Meanwhile, the orbiter probe of the ExoMars mission successfully completed its deceleration maneuver and swung into Mars orbit.

Landing on the Red Planet is anything but easy. Because the thin atmosphere of the Red Planet requires a complicated sequence of brake aids to make a larger probe safe and especially soft to put on. In fact, landing attempts have already failed, including NASA's Polar Lander in 1999.

No signal from the provincial probe

Now it seems almost as if even the attempt to land a European-Russian probe on the Red Planet for the first time could have failed. Schiaparelli's planned landing date was the afternoon of 19 October 2016 at 16:48 our time. Previously, the Landesonde had entered the Martian atmosphere at 16:42 as planned, as confirmed by a final signal.

Because the signals from Mars take about ten minutes to reach us, the ground station of the ESA did not expect the first signal after landing until 17:00 - but it did not happen. At first, this was not a cause for concern, aerospace engineers said. Because the signal of the lander is so weak that the Giant Metrewave Radio Telescope (GMRT) in the Indian Pune may not register it.

Certainty should bring the much closer receiving antennas of the orbital probes Mars Express and Mars Reconnaissance Orbiter (MRO). They orbit Mars and can therefore serve as relay stations for the Landesonde. But during the night, they also failed to receive a signal from Schiaparelli. display

Last data comes from the Martian atmosphere

The last sign of Schiaparelli's life has been captured by the ExoMars mother probe TGO: "The orbital probe has received data from the land probe that collected it during its flight through the Martian atmosphere, " ESA scientist Andrea Accomazzo reported this morning at a press conference.

In the first few minutes after entering the atmosphere, the probe slowed down from an initial speed of about 21, 000 kilometers per hour to just under 2, 000 km / h due to its heat shield. A supersonic parachute should then slow down the probe to just over 1200 km / h after breaking off the heat shield.

Whether the parachute was released and later jumped on the Bremsd sen is not known. ESA

"Heat shield worked"

As the ESA reported, this step seems to have worked out. From the data recorded by the orbiter probe, it appears that the provincial probe has successfully completed the first part of its flight. "The heat shield worked - it's fundamental to the success of future missions, " says Accomazzo.

The release of the parachute seems to have worked. "After this phase, however, the lander did not behave as we expected, " says the ESA scientist. On the last kilometers to the surface of Mars, brake nozzles should start and slow down the probe to only about four km / h.

Crash not excluded

According to the ESA, it is unclear whether the brake pads have started. If their ignition had failed, Schiaparelli could have crashed from a height of about eleven kilometers. Two meters above the ground, the nozzles should switch off after a brief suspension and the probe would have landed following gravity.

The ESA still can not say definitively whether Schiaparelli has collapsed, the height and how badly he was damaged. However, attempts are still being made to intercept a signal from Schiaparelli when the NASA orbital probes MAVEN and Mars Reconnaissance Orbiter fly over. The Giant Metrewave Radio Telescope in Pune is still on reception.

Should Schiaparelli have expected to land safely on Mars and have only communication problems, then his batteries will last another three to ten days. In this time frame, it might still be possible to get data and signals from the probe should it have survived its approach.

Success for the orbital probe

While the fate of Schiaparelli is still uncertain, the ExoMars mother probe "Trace Gas Orbiter" has successfully completed its braking maneuver: it entered a Mars orbit as planned last night. The ESA ground station received the confirmation signal at about 6:34 pm of our time after the orbiter probe returned to Mars.

The TGO probe is also considered an important building block for the next ExoMars mission in two years. By 2020, a first European Mars rover will be sold on the Red Planet. Whether his landing succeeds remains to be seen.

(ESA, 20.10.2016 - NPO)