Phoenix prepares to flex its muscles
Cyber limb extends today
NASA is preparing to flex the robotic arm on its Phoenix lander following a technical glitch which provoked a temporary comms breakdown between the spacecraft and the Mars Reconnaissance Orbiter, which relays commands to Phoenix and dispatches information from the Martian surface back to Earth.
NASA explains : "The UHF radio system used by the orbiter to communicate with the lander had gone into a standby mode earlier Tuesday for a still undetermined cause. This prevented sending Phoenix any new commands from Earth on Tuesday. Instead, the lander carried out a backup set of activity commands that had been sent Monday."
However, the orbiter last night "successfully received information from the Phoenix Mars Lander", which was duly sent Earthwards. It included "data collected by Phoenix during the mission's second day after landing on Mars".
The data bundle included a preliminary weather report from the Phoenix Weather Station (clear skies, temperatures between -80°C in the early morning and a balmy -30°C in the afternoon, average pressure of 8.55 millibars, wind speed 20km/h per hour from the northeast), plus some new snaps from the surface.
With the Mars Reconnaissance Orbiter's communication relay system currently in "a standby mode", NASA will today use its Mars Odyssey Orbiter  as intermediary to send commands to Phoenix, specifically "taking more pictures of the surroundings and making the first movements of the mission's crucial robotic arm". The agency notes : "A covering that had shielded the arm from microbes during its last few months before launch had not fully retracted on landing day, May 25, but it moved farther from the arm during the following day".
Fuk Li, manager of the Mars Exploration Program at NASA's Jet Propulsion Laboratory, Pasadena, assured: "The biobarrier had relaxed more and allows more clearance, but it was not a major concern either way."
The arm's deployment will begin with it "unlatching the wrist, then moving the arm upwards in a stair-step manner". Over the next three months, it will excavate soil and water ice samples to instruments on the lander's deck to determine "whether some chemical ingredients of life are preserved in the icy soil".
NASA on Monday released further Phoenix mission pics, including this fetching pose showing the US flag and a mini-DVD from the Planetary Society containing "a message to future Martian explorers, science fiction stories and art inspired by the Red Planet, and the names of more than a quarter million Earthlings."
Far more spectacular, though, is this view of Phoenix descending to the Martian surface on 25 May, caught by the Mars Reconnaissance Orbiter's HiRISE camera (bigger version here ):
NASA explains that while the lander appears to be heading into the 10 km-wide Heimdall crater in the background, it's actually a safe 20 km in front of the feature.