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Cloud forces shuttle launch delay Endeavour prepares for second go
(about 17 hours later)
Low cloud at the Kennedy Space Center in Florida has prevented the shuttle Endeavour from launching on its latest mission to the space station. The US space agency (Nasa) will try again in the next few hours to launch its shuttle Endeavour into orbit.
Nasa officials stood the orbiter down with under 10 minutes left on the countdown clock. Sunday's attempt at a lift-off was thwarted by thick, low cloud over the Kennedy Space Center.
Endeavour encountered no technical issues as it prepared to lift off and will try again on Monday morning. If it does get away this time, Endeavour should make a small piece of history by becoming the last shuttle to lift off in darkness.
It will be delivering a connecting unit and a large bay window to the international orbiting platform. It will be delivering a connecting unit and a large bay window to the International Space Station (ISS).
The shuttle mission is the first since President Barack Obama announced a new vision for US human space exploration. Endeavour is fuelled and ready to go, with mission control reporting no technical issues with the orbiter.
Last Monday, he cancelled the rockets and capsule Nasa was developing to replace the shuttle, and urged the commercial sector to provide future transport needs. Weather forecasters say there is a 60% chance of favourable conditions holding over the Space Coast at the time of launch, which is scheduled for 0414 local time (0914GMT).
NODE 3 - 'TRANQUILITY' Key unit connects and helps manage other ISS modulesMultiple docking ports for visiting vehicles or future modules7m by 4.6m; a mass of 14 tonnes, but will be fitted out in orbitSophisticated life support systems will include air cleaning unitCupola to be fixed to an Earth-facing port once in orbitPanoramic views provide ideal control room for robotic armNamed after Sea of Tranquility, the Apollo 11 landing siteNODE 3 - 'TRANQUILITY' Key unit connects and helps manage other ISS modulesMultiple docking ports for visiting vehicles or future modules7m by 4.6m; a mass of 14 tonnes, but will be fitted out in orbitSophisticated life support systems will include air cleaning unitCupola to be fixed to an Earth-facing port once in orbitPanoramic views provide ideal control room for robotic armNamed after Sea of Tranquility, the Apollo 11 landing site
Sunday's launch was postponed because the thick layer of cloud which moved in over Kennedy would have prevented launch officials from following visually the progress of the ascent, but also because the cloud would have hampered the safe return of the shuttle to Kennedy were it to encounter a problem and need to abort its flight. If the shuttle does not make it off the pad on Monday, it will be stood down for a few days to give ground crews a rest and allow a rocket on the nearby Cape Canaveral Air Force Station the opportunity to launch.
The head of the US space agency, Charlie Bolden, was in attendance at Kennedy.Speaking to reporters, he conceded Mr Obama's new path was causing anxiety among Nasa workers and in Congress. The main purpose of Endeavour's 13-day mission is to fit the Node 3 and Cupola modules to the ISS. Once this is done, the platform will be 90% complete.
"This is going to be complex and complicated, and we've got to work all this stuff out," he said. The mission is an important moment for the European Space Agency's (Esa) contribution to the station project. Both the modules were manufactured in Italy by Thales Alenia Space.
Endeavour's 13-day mission, which includes three spacewalks, will be the last night launch for a shuttle. The four missions that follow Endeavour will all take place in daylight hours. Node 3, also known as Tranquility, will house the station's core life-support systems.
Once installed on station, the Node 3 and Cupola modules will make the platform 90% complete. It will also store a treadmill the crew must use regularly to exercise their bodies and maintain bone density.
The mission is an important moment for the European Space Agency's (Esa) contribution to the ISS project. Both modules being ferried to orbit were constructed in Italy by Thales Alenia Space. One of the risks of living in microgravity conditions is that bones tend to lose strength over time.
Node 3 connecting unit will house the station's core life-support systems. The Cupola will afford spectacular views of Earth
The node has several berthing ports that could conceivably even allow the ISS to be expanded one day. The Cupola is an observation tower that will be used to control robots working on the exterior of the platform.
"Node 3 is an interconnecting module," explained Simonetta Di Pippo, Esa's director of human spaceflight. It is constructed in the shape of a dome, with six trapezoidal side windows and a circular top window of a little under 80cm, making it the largest window ever built for space.
"It's a door open to the future, because if we decide to develop new modules, new extensions, new capabilities, we will be able to do it because we are now launching Node 3." The Cupola is travelling into orbit attached to the end cone of Node 3 but once in orbit will be transferred to a berthing point that looks straight down to Earth.
The Cupola is a dome-shaped module with seven windows. At 80cm (31.5in) in diameter, its top window will be the biggest ever flown in space. The spectacular views from the Cupola mean it is likely to become a popular place on the station for astronauts to relax.
The module will act as a control room to direct robotic operations on the exterior of the platform, and provide a vantage point for the astronauts to view their home planet. Esa's project manager on Node 3 and the Cupola, Philippe Deloo, told the BBC: "I heard that on orbit the most favourite past-time of the crew when they're off duty is to watch out the window and look at Earth.
"The psychological effect of being able to look outside, to look at the Mother Earth, is something that has long been put forward as an argument to have windows on the station."
Endeavour's crew is commanded by George Zamka, a colonel in the US Marine Corps; and includes the British-born mission specialist Nicholas Patrick.
Dr Patrick will conduct the three spacewalks to install the two modules with colleague Bob Behnken.
Behnken and Patrick (far left) will undertake the three spacewalks
Jonathan.Amos-INTERNET@bbc.co.ukJonathan.Amos-INTERNET@bbc.co.uk