NASA officials are wrestling with why the Phoenix Mars lander wound up shooting long within a pre-designated landing ellipse.

A better understanding of why Phoenix and several other Mars landings have made less than bulls-eye touchdowns is being flagged by NASA space science chief, Ed Weiler. It’s an issue that needs to be resolved, particularly given the accuracy needed for the NASA’s next Mars lander - the super expensive mega-rover, the Mars Science Laboratory.

Mars exploration program officials, for example, are curious whether or not Mars atmospheric models are accurate - or is something else at work in the entry, descent and landing profiles of Mars probes that’s not up to snuff.

In a related development, NASA is preparing a formal request to the European Space Agency to request that ESA’s Mars Express orbiter be used as standby to support Phoenix lander operations.

NASA’s Mars Reconnaissance Orbiter is experiencing on-going glitches in using its UHF link to Phoenix. That intermittent problem means more reliance on Odyssey, NASA’s other Mars orbiter.

ESA’s Mars Express is viewed as added assurance beyond Odyssey that the Phoenix Mars lander can fulfill its scientific duties over the months to come.