Scheduled For 1630 EDT
Three hours ago, NASA began
the countdown for the launch of Space Shuttle Atlantis on mission
STS-115, at the T-minus 43 hour point. During this mission,
Atlantis' crew will resume the construction of the International
Space Station -- the goal of the remaining space shuttle flights in
the program.
The Kennedy Space Center launch team will conduct the countdown
from the newly renovated Firing Room 4 of the Launch Control
Center. The countdown includes 33 hours, 24 minutes of built-in
hold time leading to a preferred launch time at about 4:30 pm on
Sunday, August 27, with a launch window extending about five
minutes.
This mission is the 116th space shuttle flight, the 27th flight
for orbiter Atlantis, and the 19th US flight to the International
Space Station. STS-115 is scheduled to last 11 days, with a planned
return to Kennedy Space Center at about 12:02 pm EDT on September
7.
Atlantis rolled into KSC's Orbiter Processing Facility on
October 18, 2002, after returning from its last mission, STS-112.
Its next mission was planned to be STS-114; however, during the
program delays following the 2003 loss of Columbia, Atlantis was
reassigned to mission STS-115. The orbiter rolled out of the
facility's bay 1 and into the Vehicle Assembly Building on July
24.
While in the building's high bay 3, Atlantis was mated to its
modified external tank and solid rocket boosters. The entire space
shuttle stack was transferred to Launch Pad 39B on August 2.
The STS-115 crew includes Commander Brent Jett, Pilot Chris
Ferguson, and Mission Specialists Joe Tanner, Dan Burbank,
Heidemarie Stefanyshyn-Piper and Steve MacLean of the Canadian
Space Agency.
During mission STS-115, Atlantis will dock with the station and
the crew will perform three spacewalks. The astronauts will deliver
and install the 17.5-ton, bus-sized P3/P4 integrated truss segment
to the station's girder-like truss backbone. The new piece will
include a second set of giant solar arrays, batteries and
associated electronics. Together, the trusses and solar arrays will
provide one-fourth of the total power-generation capability of the
completed station.
To prepare for the extravehicular activities, the spacewalkers
will perform a new "campout pre-breathing exercise." These crew
members will reside in the station's airlock overnight, where the
pressure will slowly be reduced. Harmful gases will thereby be
removed from their blood, allowing them to gradually acclimate to
the lower pressure they will encounter outside the station.
Provisions are onboard to support as many as three additional
spacewalks, if required to complete mission objectives.