Plans for the Phoenix Mars Lander's second day of activities on Mars have been delayed, Nasa officials said today.
A problem in relaying communications from one of two Mars orbiters relaying commands from Earth has caused the delay.
Fuk Li, manager of the Mars exploration programme for Nasa's Jet Propulsion Laboratory in Pasadena, California, said that a "transient event" on the Mars Reconnaissance Orbiter turned its UHF radio off. That stopped communications between it and the lander.
Mr Li said it was not a significant problem, however.
Peter Smith of the University of Arizona, the mission's principal researcher, said it had been hoped for the lander's 8ft robotic arm to be unhooked from a latch holding it in place today.