* Launch delayed at least until Monday
* Obama meets shuttle crew, astronaut wife Giffords
* Heaters on power unit failed four hours before launch
(Updates with Obama met Giffords)
By Irene Klotz and Alister Bull
CAPE CANAVERAL, Fla., April 29 NASA delayed
Friday's launch of space shuttle Endeavour because of a glitch
but the grounded crew and the commander's wounded wife got a
chance to greet President Barack Obama as he toured the Kennedy
Endeavour's launch was scrubbed four hours before liftoff
after the heaters failed on one of the ship's power units. NASA
said it would be at least Monday before it could try again to
launch Endeavour on its final voyage.
U.S. Representative Gabrielle Giffords, who is married to
Endeavour commander Mark Kelly, was on hand for the launch. The
Arizona Democrat was gravely injured during an assassination
attempt on Jan. 8 and had not been seen publicly since then.
Obama met privately with Giffords before greeting the six
crewmen, the White House said.
"I bet you were hoping to see a rocket launch today," Kelly
told the president.
Endeavour had been filled with 500,000 gallons (1.9 million
litres) of supercold liquid oxygen and liquid hydrogen in
preparation for a launch attempt at 3:47 p.m. EDT (1947 GMT).
The astronauts were on the way to the launch pad when the
flight was called off.
"Unfortunate for the (Endeavour) team and Mark Kelly and
his crew, but today the orbiter is not ready to fly and as we
always say in this business, we will not fly before we're
ready," said launch director Mike Leinbach.
The failed heaters are on one of the shuttle's three
onboard generators that provide hydraulic power for the
Leinbach said it would be at least 72 hours before there
could be another launch attempt.
Endeavour is to deliver a high-profile physics experiment
to the International Space Station. The mission is the 134th
and next to last for the U.S. space shuttle program, which is
ending after a cargo run by the shuttle Atlantis this summer.
Endeavour was the replacement ship for Challenger, which
was lost in a fatal 1986 launch accident. It is the youngest of
NASA's three surviving spaceships and the second to be
Discovery, the fleet leader, returned from its final space
mission in March, and Atlantis is due to end the 30-year-old
shuttle program with a launch on June 28.
Obama, who had been scheduled to watch the launch with his
wife and daughters, got a close-up look at Atlantis inside a
hangar where it is being readied for launch. They stood under a
wing as NASA workers explained how the ship's thermal tiles
keep it from burning up when it re-enters the atmosphere.
"Where is the duct tape?" Obama joked.
The shuttle Columbia was destroyed due to a damaged heat
shield as it flew through the atmosphere for landing in 2003.
Endeavour's last flight is devoted to outfitting the space
station, a $100 billion project of 16 nations, with its
highest-profile science instrument, a $2 billion particle
detector called the Alpha Magnetic Spectrometer.
The instrument was built by an international collaboration
of 60 research organizations and overseen by Nobel physics
laureate Samuel Ting of the Massachusetts Institute of
The device is designed to study high-energy particles in
cosmic rays, gathering information that could help scientists
better understand "dark matter," which cannot be directly
Endeavour also carries spare parts for the station, which
will soon be dependent on smaller cargo ships from Russia,
Europe and Japan for resupply missions. NASA has hired two U.S.
companies, Space Exploration Technologies and Orbital Sciences
Corp ORB.N, to join the cargo runs beginning next year.
(Editing by Jane Sutton and Eric Walsh)