LONDON — Scientists at a British observatory, listening for a signal from Europe’s first Mars lander, failed to determine Thursday if the Beagle 2 arrived on the Red Planet, a government agency said.

More than 19 nail-biting hours after the tiny craft was to have rolled to a stop on the surface of Mars, the radio telescope at Jodrell Bank Observatory in Cheshire, England, took advantage of the planet’s position to begin scanning its surface for the Beagle’s signal — about as powerful as that of a cell phone’s.

Between the hours of 5 p.m. and 7 p.m. EST, which would be at the end of the Martian night, they listened for the Beagle’s signal.

"Jodrell Bank listened out for Beagle 2 tonight, but did not detect a transmission," the physics and astronomy research agency said in a statement. It said the next chance will come this evening.

Earlier, European space officials cheered as Beagle 2’s experiment-crammed Mars Express mother ship successfully slid into Martian orbit. That was a make-or-break task since the craft is supposed to beam back the data gathered by the lander from the surface, as well as do its own scanning and mapping.

The $370 million mission aims to search for evidence of life on Mars. Beagle was supposed to have plunged into the Martian atmosphere for 7 1/2minutes and landed on the surface at 9:45 p.m. EST Wednesday, its impact softened by parachutes and gas bags. Once there, its antennae were to flip open and begin transmitting home.

A separate craft already in orbit — the U.S. Mars Odyssey — couldn’t detect the probe’s signal on its first pass over the landing site.

"It’s a bit disappointing but it’s not the end of the world. Please don’t go away from here believing we’ve lost the spacecraft," said Colin Pillinger, Beagle 2 project’s lead scientist.

Officials said the 143-pound Beagle could have landed with its antenna pointing at the wrong angle for Odyssey, or the Martian cold could have distorted the radio frequency it emits.

But space scientists said they had several more chances to hear from it and remained optimistic about Europe’s first mission to search for signs of past or present life on Mars.

Also, the Mars Express, which turned Beagle loose six days earlier, should be able to make contact with the lander in a few days after adjusting its orbit.

Early Thursday, controllers at the European Space Agency center at Darmstadt clapped and hugged each other when a big screen showed blips indicating they had regained the orbiter’s data feed after it emerged from behind Mars following its first circle.

"At least the initial checks show that the spacecraft is in very good condition," said flight director Michael McKay.

David Southwood, the space agency’s science director, said it was "a wonderful Christmas morning."

The maneuver began with Mars Express firing its main engine to slow it into orbit.

Several hours of tense waiting followed after the craft ceased sending data, having turned its main antenna away from the Earth so it could point its engine in the right direction.

Intricate maneuvers are still ahead. Controllers must change the orbit of Mars Express from a high elliptical one around the equator to a lower polar orbit that will let it cover more of the surface with its instruments.

Still, the Mars Express orbit maneuver was a major success for the agency’s first mission to another planet.

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