Posted: Wed, Apr 3, 2002, 9:07 AM ET (1407 GMT)
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The countdown for Thursday's launch of the shuttle Atlantis on mission STS-110 began on Monday, still shrouded in secrecy, NASA officials confirmed Tuesday. The news was not unexpected, since a Thursday afternoon launch would have normally required the countdown to begin on Monday. The exact launch time will be announced by NASA Wednesday afternoon, 24 hours before the launch; NASA has only said that the launch will take place between 2 and 6 pm EST (1900-2300 GMT), but outside analysts have estimated a launch time of approximately 5:15 pm EST (2215 GMT) based on the orbit of the space station. Technicians are checking the motors on a door in the shuttle's underside that closes after the external tank jettisons, but NASA officials say they are optimistic that the door will check out fine. Meteorologists are forecasting a 70 percent chance of acceptable weather Thursday afternoon. Atlantis will dock with the International Space Station and install the first segment of the station's truss.