From the NASA Phoenix Mission site:
The launch of the Phoenix spacecraft has been rescheduled to Aug. 4.
Due to the forecast for severe weather in the vicinity of the launch
pad on Tuesday afternoon, the Delta II launch team was unable to
complete fueling of the rocket's second stage. The two available launch
times on Aug. 4 are 5:26:34 and 6:02:59 a.m. EDT.
Mars lander's assignment is to dig through the Martian soil and ice in
the arctic region and use its onboard scientific instruments to analyze
the samples it retrieves.
Both rocket and spacecraft have been undergoing final preparation at NASA's Kennedy Space Center in Florida.
For more information about the Phoenix mission, visit: http://www.nasa.gov/phoenix
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