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BERLIN, Oct. 19 (Xinhua) -- European Space Agency (ESA) announced at its mission control center in German city of Darmstadt on Wednesday evening that its Mars exploration project ExoMars had arrived at the Red Planet after receiving signals from the Trace Gas Orbiter (TGO).

However, the ESA could not get the signals from the Schiaparelli lander as it was supposed to land at 4:48 p.m. local time in Germany (1448 GMT), because radio contact was lost before landing.

At this moment, it is unclear how Schiaparelli landed or whether it is harmed.

"The ground control team at ESA's space operations center are going to work all night to analyze the data on the ExoMars Schiaparelli lander. More at the press conference tomorrow," the ESA said on its Facebook account.

ExoMars, a joint endeavor between the ESA and Russia's Roscosmos space agencies, comprises the TGO and the Schiaparelli lander.

TGO is on a multi-year mission to understand the methane and other gases in Mars' atmosphere at low levels, and could be evidence for possible biological or geological activity, while Schiaparelli lander will test key technologies in preparation for ESA's ExoMars 2020 rover mission.