28 Oct 2016

With a clear mind and having analysed the data, we can now say that the first part of the ExoMars mission, with the Schiaparelli lander and the TGO orbiter, was largely successful and opens up the way to the continuation of this ambitious European mission in which Italy plays a vital role

At 4:48 pm on 19 October, the ESA module, Schiaparelli, should have touched the surface of Mars, telling us that everything had gone according to plan. It did indeed touch the surface of Mars, but with greater momentum than expected. For this reason, the day of 19 October went by, while we waited to find out what had happened. On 20 October, an ESA press conference told us the story, based on the data collected during the night, though there is more data to come.
This data does, however, demonstrate the success of the mission, specifically this first part of it, leaving us optimistic about the continuation of the ExoMars mission, which should be sanctioned by an ESA ministerial decree in December this year, in Lucerne, Switzerland, as the President of ASI, Roberto Battiston, pointed out: “On the whole, we are encouraged to continue on with our work for ExoMars 2020, one of the key topics of the ministerial decree.”

So, let’s try to summarize what happened and what we have obtained: after along interplanetary voyage of approximately 500 million kilometres, the descent module separated from the Trace Gas Orbiter (TGO) on 16 October and, after an approach period that lasted three days, it reached the outer limit out the atmosphere of Mars, the so-called “entry interface point” at approximately 122 km from the surface of the planet, at which time it began its final descent to Mars at a speed of approximately 21,000 km/h.
Schiaparelli successfully completed most of the planned phases during the long-awaited and critical six-minute descent in the atmosphere of Mars, like deceleration through the atmosphere and the opening of the parachute and of the thermal shield. The propulsors were briefly activated. However, it seems probable that they shut down earlier than anticipated, at an altitude that is still to be determined. This is the result of the partial analyses, currently underway, of the data that Schiaparelli sent to the mother probe during the descent phase.

During the lander’s descent, the orbiter correctly entered into the elliptic orbit around Mars with a 7.4° inclination and an orbital period of four days. The module will maintain this position until January 2017, when the inclination will be increased to 74° and the orbital period will be reduced to 1 day. From March 2017 the Orbiter will begin to gradually circularize the orbit with a mechanism of friction braking with the Martian atmosphere (Aerobraking) using the large surface of its solar panels.
The scientific mission of the ExoMars orbiter is to analyse the atmosphere of the planet, searching for traces of methane, in particular, and determining their concentration and distribution. In the event that any methane is identified, scientists will establish whether or not its origin is biological or geological.

Now let's look at the questions that are still open and at may receive an answer in the coming weeks: first of all, if the retrorockets shut down due to a wrong impulse of the on-board software or because they malfunctioned or, lastly, because “backing off the throttle”, as they say in motor racing, did not function properly and Schiaparelli went “too far”.
Is there any hope that it will start sending signals again? Not much, but every attempt will be made to resume contact and, for example, to download any missing data, meaning the data that could not be recovered when the lander shut down - always assuming that the shutdown took place before the crash and not simultaneously.

Lastly, there are two aspects to consider: of the experiments on the lander, the Italian AMELIA did its duty and, together with the TGO on the orbiter, operates two experiments with the co-participation of the Italian National Institute of Astrophysics, the Belgian NOMAD and CaSSIS. One thing is certain: INAF (Italian National Institute of Astrophysics) will be there in 2020, as its president, Nichi D'Amico, pointed out: “The Italian National Institute of Astrophysics is undoubtedly ready to continue developing the scientific instrumentation for the second part of the mission.”
The CEO of Thales Alenia Space Italia, Donato Amoroso, also appears to be satisfied: “We are at the first fundamental stage of an extraordinary international programme, which is the result of cooperation between agencies and industry. In fact, we have an orbiter around Mars, that is useful and precious for the future ExoMars 2020 mission, the aim of which is to place a European rover on Mars.”

Notes: The ExoMars programme is the result of cooperation between the European Space Agency (ESA), the Russian Space Agency (Roscosmos) and the Italian Space Agency (ASI). The ExoMars 2016 mission consists of an orbiter, the TGO (Trace Gas Orbiter), assembled at the Thales Alenia Space site in Cannes, with three scientific instruments and a high-resolution camera on board, and of a descent module, the EDM (Entry descent landing Demonstrator Module), which was assembled at the Turin site, equipped with scientific instruments for the physical and meteorological characterization of the atmosphere of Mars, a laser reflector and a video camera that is active during descent.
Leonardo-Finmeccanica also contributed to ExoMars 2016, providing star trackers, photovoltaic panels, electronic supply units and the optronic heart of the video camera, CASSIS. Leonardo is also developing the diamond-drill that will set off in 2020 to dig into the surface of Mars to a depth of 2 metres, in search of traces of life.

Lastly, Telespazio (Leonardo-Finmeccanica 67%, Thales 33%) is responsible, through the subsidiary Telespazio VEGA Deutschland, for the development of several key systems of the earth segment of the mission.