Saturday's scheduled launch of NASA's Dawn spacecraft aboard a United Launch Alliance Delta II rocket has been postponed 24 hours.
A lightning advisory early Thursday interrupted fueling of the Delta II second stage rocket. Also, the temperature of the vehicle's second stage was too warm for the fueling process to begin. However, the fairing temperature has been lowered so that another attempt can be made Friday, July 6, pending acceptable weather.
Dawn's launch countdown dress rehearsal is now scheduled for Friday. The launch window on Sunday, July 8, extends from 4:04 p.m. to 4:33 p.m. EDT.
Weather for launch still may be an issue with a 60% chance of it not meeting launch criteria on Sunday.
The Dawn mission science briefing, scheduled for Friday, will be held as planned at 1 p.m. The pre-launch news conference is scheduled for 1 p.m. Saturday, July 7, following the Launch Readiness Review.
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