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Radio link with Mars lander restored

A communication problem for NASA's Phoenix lander has been resolved, but it's still not clear what caused the glitch
The Mars Reconnaissance Orbiter relayed this image from Phoenix after the radio link was restored
The Mars Reconnaissance Orbiter relayed this image from Phoenix after the radio link was restored
(Image: NASA/JPL-Caltech/University of Arizona)

A key communication link with NASA鈥檚 Phoenix lander has been restored, after an outage delayed the mission鈥檚 progress by one day.

Phoenix landed flawlessly on Mars on Sunday afternoon PDT (early Monday morning GMT) and quickly started sending back images from the surface. Although Phoenix remains in good health, a problem cropped up on Tuesday morning PDT (Tuesday afternoon GMT), when NASA had trouble uploading new commands to the lander.

Phoenix does not communicate directly with Earth. Instead, radio transmissions are relayed between Phoenix and Earth by two NASA spacecraft in orbit around Mars.

The glitch happened when the UHF radio on one of the two spacecraft, NASA鈥檚 Mars Reconnaissance Orbiter (MRO), failed to relay a sequence of commands from Earth, intended to guide Phoenix through the second day of its mission.

Because Phoenix did not receive any fresh instructions, it performed what is known as a 鈥渞un-out sequence鈥, which amounts to a continuation of the previous day鈥檚 activities.

Now, MRO鈥檚 UHF radio has started working again. On Tuesday evening PDT (early Wednesday morning GMT), it successfully relayed images and other data from Phoenix back to Earth.

NASA has determined that MRO鈥檚 UHF radio unexpectedly went into standby mode earlier on Tuesday, though why this happened is still unknown.

NASA鈥檚 Mars Odyssey orbiter can step in if further communication problems occur. If necessary, communications can be routed entirely through Mars Odyssey for the duration of Phoenix鈥檚 90-day mission on the Red Planet.

Mars Rovers 鈥 Mars is full of surprises, learn more in our continually updated .