Fears grow that ExoMars lander lost in final minute of descent

The ExoMars lander seems to have been lost. In a press conference this morning, ESA spelled out what we know so far about what happened to the Schiaparelli lander on its descent to the surface of Mars.

About 50 seconds before touch down, the lander lost communication. It had successfully used its heatshield to slow down as it entered the Martian atmosphere and deployed its parachute. The parachute was then meant to be ejected and thrusters turned on to prepare Schiaparelli for landing, but this is where things went wrong.

“There is a point where the parachute is released where the data we have collected from Schiaparelli does not quite match our expectations,” said Andrea Accomazzo, ESA Spacecraft Operations Manager.

The data is still be analysed, but there was radio silence for the final part of the descent.  “What is the likelihood the lander is in one piece?” said Jan Wörner, ESA Director General. “We don’t know.”

The press questions focussed on Schiaparelli, but ESA were keen to explain that much of the mission has been successful.  Schiaparelli arrived with the Trace Gas Orbiter (TGO), which has been successfully put into orbit around the Red Planet.

“TGO is now ready for science. We got all of the confirmations that we needed,” said Wörner. TGO will start its science mission in 2017, after slowly moving into a more stable orbit around Mars.

Over the next few days ESA have a few opportunities to find out exactly what has happened to Schiaparelli. The lander was not designed for interactive communication, but if it hasn’t been destroyed, ESA does have the capability to reset its on-board computers and transmitters using TGO. It’s possible that Schiaparelli landed successfully and is just having technical trouble, so a reset could help.

There will also be a chance to take a picture of the landing area with NASA’s Mars Reconnaissance Orbiter. Schiaparelli will appear very small, but it could help to explain what’s happened.

ESA are working against the clock. Schiaparelli’s batteries are only expected to last somewhere between 4 to 12 days. If they are going to make the most of the lander, they’ll need to re-establish communication soon.

David Parker, ESA Director of Human Spaceflight and Robotic Exploration, concluded the press conference by saying:  “Mars exploration is hard, and that’s one of the reasons that we do it.”

Not good signs

There was always a risk that this would happen. In practice tests, it was possible to track Schiaparelli throughout all of its landing procedure. But practice is not the same as the real thing. Lots of different factors could cause a lack of communication, such as the orientation of the probe.

“We waited for the Mars Express measurement which was taken in parallel,”Paolo Ferri, ESA head of missions operations, said last night. “It was of the same kind, it was only recording the radio signal. The signal came through at 6.30pm and confirmed exactly the same.

“The signal went through the majority of the descent phase, but it stopped at a certain point that we reckon was before the landing. To conclude more on this, because there can be many, many reasons for that, we need more information. It’s clear these are not good signs.”

Last night Ferri said their objective was to have a “very good story” before this morning’s press conference or they would look a “bit hopeless”.

Schiaparelli was only the second probe ESA has attempted to land on Mars. The first, Beagle 2, also suffered a radio blackout after detaching from its Mars Express mothership on Christmas Day 2003.

Anxious minutes of waiting turned into hours and days until scientists finally had to admit that the British-built craft was lost.

It was not until last year that scientists discovered the probe on the surface of Mars. Satellite images suggested two solar panels had failed to deploy, blocking its communications antenna.

A lot rides on this landing’s success. The ExoMars mission ultimately aims to land a rover on Mars in 2021, and so the two agencies involved – ESA and Roscosmos – have to show they are capable of doing so.

ExoMars Rover will send a six-wheeled mobile laboratory built in the UK to the Red Planet to drill for soil samples and analyse them for signs of past or present life.