Discovery shuttle makes historic last touchdown
12 March BBC
The most-travelled of America's space shuttles, Discovery, has
brought its remarkable 27-year career to an end. The orbiter has just
landed at the Kennedy Space Center in Florida after a 12-day - and final
- mission to the International Space Station (ISS).Discovery is destined
now to go to a museum. Nasa's two other reusable spaceplanes will follow
it into retirement in the coming months.
The landing at Kennedy occurred just before midday, local Florida
time. On its final flight, Discovery delivered a new store room and a
sophisticated humanoid robot to the ISS.
The ship's crew also performed two spacewalks to carry out
maintenance tasks on the exterior of the platform.
The final act in Discovery's career was initiated with a two-minute,
31-second burn from its thrusters. This dropped the ship out of orbit
and into a re-entry path that took it across the Pacific, over Central
America and the Gulf, before a last sharp banking manoeuvre and a
touchdown on Kennedy's Runway 15 at 1157 and 17 seconds EST (1657:17
GMT).
"Houston, Discovery for the final time - wheels stop," Commander
Steve Lindsay radioed to Mission Control in Texas."Job well done," was
the reply from astronaut Charlie Hobaugh, who was acting as the Capsule
Communicator, or Capcom, in Houston. "You were able to take Discovery up
to a full 365 days of actual time on orbit. I think you'd call that a
fleet leader, and a leader of any manned vehicle for time in orbit."
Already, Nasa is looking forward to the next mission. In just a few
hours, shuttle Endeavour will roll out of Kennedy's vast Vehicle
Assembly Building to go to the launch pad in preparation for its final
voyage into space next month.The Atlantis orbiter will close the shuttle
programme with a flight in June or just beyond.
The plan then is for US astronauts to be transported to the ISS on
Russian Soyuz rockets, perhaps until the middle of the decade. A number
of American companies should be in a position by that stage to sell
launch services to Nasa on a range of new vehicles.Such matters, though,
are secondary on what is undoubtedly a day of high emotion. Eileen
Collins was the first woman to pilot a shuttle, and commanded Discovery
in 2005 on the "return to flight" mission after the Columbia accident.
"The shuttle-in-general's biggest achievement, I believe, was
building the International Space Station, which is pretty much 99%
complete - and Discovery was part of doing that," she told BBC News."But
also Discovery took up the Hubble Space Telescope and also visited the
Mir space station, and did many satellite deploys and spacelab missions
prior to the space station.
"When you look at the shuttle programme as a whole, we have learned
not only to fly space shuttles to low-Earth orbit and re-use them, but
we've learned about the environment of space and how to make future
spacecraft better through the mistakes that were made in the shuttle
programme. So overall I think the shuttle was a huge success."
Endeavour's scheduled lift-off date is 19 April. It will deliver a
flagship scientific experiment to the ISS known as the Alpha Magnetic
Spectrometer (AMS).
This seven-tonne instrument will sit on the platform's truss, or
backbone, to conduct a survey of cosmic rays.
Researchers hope this study will reveal new insights into the make-up
and origin of the Universe.Endeavour will be commanded by astronaut Mark
Kelly, whose wife, Congresswoman Gaby Giffords, is still recovering from
a bullet wound to the head sustained during an assassination attempt in
January. |