Europe's second attempt to reach Mars' surface appeared in peril Thursday as initial analysis suggested the latest lander may have plummeted to its demise.

While holding out faint hope, ground controllers said it seemed the paddling pool-sized lander's parachute may have been discarded too early, and its fall-breaking thrusters switched off too soon.

The lander, dubbed Schiaparelli, was on a test-run for a future rover that will seek out evidence of life, past or present, on the Red Planet.

But it fell silent seconds before its scheduled touchdown, while its mothership Trace Gas Orbiter (TGO) entered Mars' orbit as planned -- part of a joint European-Russian project.

"We are not in a position yet to determine the dynamic condition at which the lander touched the ground," European Space Agency (ESA) head of solar and planetary missions Andrea Accomazzo told a webcast news briefing at mission control in Darmstadt, Germany.

Further analysis must be done of some 600 megabytes of data the 230 million-euro ($251-million) craft sent home before its signal died, to "know whether it survived structurally or not."

This could take "some time", Accomazzo added.

ESA and NASA Mars orbiters, meanwhile, were keeping their eyes and ears open for any signal from the lander.

If not, this would be Europe's second failed Mars landing in a row, joining a string of unsuccessful attempts by global powers to explore our planetary neighbour's hostile surface.

The British-built Beagle 2 robot lab disappeared without trace after separating from its mothership, Mars Express, in 2003. Its remains were finally spotted in a NASA photograph last year.

Schiaparelli had travelled for seven years and 496 million kilometres (308 million miles) onboard the TGO to within a million kilometres of Mars on Sunday, when it set off on its own mission to reach the surface.

The pair comprise phase one of the ExoMars mission through which Europe and Russia seek to join the United States in probing the alien Martian surface.

The TGO is meant to sniff atmospheric gases potentially excreted by living organisms, while Schiaparelli's landing was designed to inform technology for a bigger and more expensive rover scheduled for launch in 2020.

The six-wheel rover will be equipped with a drill to look for remains of past life, or evidence of current activity, up to a depth of two metres.

While life is unlikely to exist on the barren, radiation-blasted surface, scientists say traces of methane in Mars' atmosphere may indicate something is stirring underground -- possibly single-celled microbes.

- Trial and error -

"Schiaparelli" was scheduled to touch down at 1448 GMT Wednesday after a scorching, supersonic dash through the thin atmosphere of Mars, some 170 million kilometres from Earth.

For a safe landing, it had to brake from a speed of 21,000 kilometres (13,000 miles) per hour to zero, and survive temperatures of more than 1,500 degrees Celsius (2,730 degrees Fahrenheit) generated by atmospheric drag.

It was equipped with a discardable, heat-protective "aeroshell" to shield it, and a parachute and nine thrusters to decelerate.

A crushable structure in Schiaparelli's belly was meant to cushion the final impact.

"It could be that this parachute phase has been terminated too early then we were far too high, or we have had a behaviour during the parachute phase that led the lander to be far too low," Accomazzo said.

As for the thrusters, "it seems likely that they switched off sooner than expected," added an ESA press statement.

Since the 1960s, more than half of US, Russian and European attempts to operate craft on the Martian surface have failed.

Europe has budgeted 1.5 billion euros for its share in the ExoMars project.

ESA director-general Jan Woerner stressed the successful orbit-insertion of the TGO, scheduled to start its gas-sniffing science mission in 2018.

"We have an impressive orbiter around Mars ready for science," he said.

"We are really confident that we have the right basis for a successful European science (mission) on Mars, looking for life."

Even a crash by Schiaparelli would yield important lessons for the rover, he added, and need not derail the rest of the mission for which ESA will seek additional funding from European governments in December.

"Recording the data during the descent was part of that and it is important that we can learn what happened, in order to prepare for the future."

Europe's Mars lander: What do we know?
Paris (AFP) Oct 20, 2016 - Scientists and engineers were piecing together clues Thursday to the fate of Europe's "Schiaparelli" Mars lander, which fell silent just seconds before its scheduled touchdown on the Red Planet.

Some are holding out hope, but initial data suggests the craft, a test-run for a European-Russian Mars rover, ran into trouble.

What European Space Agency (ESA) experts have gleaned so far from data Schiaparelli sent home:

Known:

Schiaparelli is on Mars.

Not known:

Where exactly, in how many pieces, or whether it is "awake".

Known:

Schiaparelli entered Mars' outer atmosphere at 1442 GMT on Wednesday, as scheduled, for what should have been a six-minute dash to the surface.

Not known:

Where the lander was when its signal dropped out, about 50 seconds before scheduled touchdown.

Known:

The first tool in Schiaparelli's defence arsenal, a shield against the scorching heat generated by atmospheric drag, had worked. If not, the next phase -- deployment of a supersonic parachute, would not have happened.

Not known:

Why the shield, with parachute attached, seems to have been jettisoned too early.

Known:

The parachute deployed.

Not known:

Whether the parachute was discarded too early, or somehow malfunctioned so that the lander was already too close to the surface when its rocket brakes kicked in.

Known:

The third piece of protective hardware, speed-breaking retro-rockets did fire but only for three or four seconds -- "much shorter than what we were expecting," according to European Space Agency (ESA) head of solar and planetary missions Andrea Accomazzo.

Not known:

Whether all nine rockets fired.

Known:

Schiaparelli has onboard batteries designed to last at least four sols (a sol is a Mars days of about 24 hours and 40 minutes), and at up to 10 or 12 sols.

Not known:

If it is intact and switched on, Schiaparelli is consuming battery power, which means time could be running out for mission controllers to try and make contact via its transceiver -- a device that can transmit and receive messages.

The lander was designed to prepare for a bigger and more expensive rover set for launch in 2020, and ESA officials insist that even a crashlanding would yield important lessons.

"The test is there to get data, to get some knowledge, and we got the knowledge, we got the data," said ESA director general Jan Woerner.

Further analysis of the information gleaned should allow for a full reconstruction of events, added Accomazzo, though this could take some time.

Source: ESA