ESA Gets Better View of Schiaparelli Impact Site, But Mysteries Remain

NASA’s Mars Reconnaissance Orbiter (MRO) has provided a higher resolution image of the site where the European Space Agency’s (ESA’s) Schiaparelli lander impacted the Martian surface, but some of the features in the image remain unexplained.  Schiaparelli is part of ESA’s ExoMars program and was designed to demonstrate technologies needed for the next phase of the program — a Russian lander and ESA rover to be launched in 2020.  Understanding exactly what happened is crucial for the 2020 mission.

Schiaparelli was launched together with ESA’s Trace Gas Orbiter (TGO) in March. The two made the trip to Mars together, separating on October 16, three days before arrival at Mars. TGO successfully entered orbit, but contact was lost with Schiaparelli during its descent. 

It was located two days later using the low resolution CTX camera on MRO.  The image indicated that the lander crashed into the surface at a high velocity after separating from its parachute and heat shield.   ESA has been awaiting a second pass over the site by MRO to obtain an image with its high resolution camera, HiRISE.

That image was taken on October 25 and released to the public today. It shows three impact areas, highlighted in the image below, within 1.5 kilometers of each other.

High resolution image of Mars surface where ESA’s Schiaparelli lander impacted, taken by HiRISE camera on NASA’s Mars Reconnaissance Orbiter, October 25, 2016.  Image credit:  NASA/JPL-Caltech/University of Arizona.  Inserts are 6-fold enlargements, brightness was adjusted separately for each inset to better show details.

As shown in the image, the parachute and the rear section of the heat shield (also called the back shell, to which the parachute was attached) landed adjacent to each other (bottom left). The front section of the heat shield separated from the rest of the spacecraft as planned and landed further away (top right).  A shallow crater, perhaps half a meter deep, in between is where the lander reached the surface and, presumably, exploded.  Data that ESA received from Schiaparelli before it went silent indicate that the parachute and back shell released prematurely and nine thrusters that should have slowed the spacecraft fired for only a few seconds, so the fuel tank would have been relatively full.  ESA estimates that the spacecraft was in free-fall for the final 2-4 kilometers of its journey and impacted the surface at a velocity of as much as 300 kilometers/hour.

ESA said today that the “asymmetric surrounding dark markings” near the crater “are more difficult to interpret.”  Also, the “long dark arc” to the upper right of the crater “is currently unexplained.”  Both could be related to the impact and presumed explosion, ESA added, but more analysis is needed.

Schiaparelli and TGO are the first two of four spacecraft that comprise ESA’s ExoMars program, which it is conducting cooperatively with Russia’s Roscosmos state space corporation.  Initially ExoMars was an ESA-NASA program, but the Obama Administration declined to fund NASA’s portion and ESA turned to Russia instead.  

The other two spacecraft — a Russian lander and an ESA rover — are scheduled for launch in 2020 (delayed from 2018). Schiaparelli was designed to test entry, descent and landing (EDL) technologies in preparation for the lander/rover mission.  Only the United States has successfully landed spacecraft on Mars. Seven of eight attempts since 1976 have succeeded:  Viking 1, Viking 2, Mars Pathfinder + Sojourner, Spirit, Opportunity, Phoenix and Curiosity.  Only the 1999 Mars Polar Lander failed.  One of the four landers sent to Mars by the Soviet Union in the 1970s sent back data after landing, but for less than 20 seconds so is not considered a success.  The United Kingdom sent the Beagle 2 lander to Mars along with ESA’s Mars Express in 2003, but it landed in a semi-deployed manner and was unable to communicate.

ESA Director General Jan Woerner stresses that TGO is fully successful and will conduct its planned science program to study trace gases in the Martian atmosphere that may reveal whether life ever existed there, and serve as a communications relay for the 2020 lander/rover.  He also considers Schiaparelli a success in the sense that entry into the atmosphere and deployment of the parachute worked as planned and they will gain data from the investigation that will be important to the success of the 2020 mission.