Tracking of the Schiaparelli robot’s radio signals was dropped less than a minute before it was expected to touch down on the Red Planet’s surface.
Satellites at Mars have attempted to shed light on the probe’s status, so far without success.
One American satellite even called out to Schiaparelli to try to get it to respond.
The fear will be that the robot has crashed and been destroyed. The European Space Agency, however, is a long way from formally calling that outcome.
A Schiaparelli crash could impact plans for the 2020 rover, though that mission is now using a different type of landing system, ESA scientist Olivier Witasse said during a webcast press conference at the American Astronomical Society meeting in Pasadena, California.
Landing on Mars, currently some 35 million miles (56 million km) away from its nearest planetary neighbour Earth, is a notoriously difficult task that has thwarted a single previous effort by Europe, most of Russia’s probes and given US space agency NASA’s trouble as well.
The planet’s hostile environment has not detracted from its allure, with US President Barack Obama recently highlighting his pledge to send people to the surface by the 2030s.
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