This afternoon space shuttle Discovery will return to earth and land at Florida’s Kennedy Space center at 13.02 EST. In preparation for the return home, the crew (shown above) tested flight control systems and thruster jets, stowed equipment and installed a special reclining seat for Clayton Anderson, who is returning after more than five months on board the International Space Station.
The Crew on board Discovery
A one minute, 58 second deorbit burn will slow Discovery by 148 miles per hour (217 feet per second) for the reentry across the heartland of the United States traveling from the northwest to southeast.
If weather conditions will not be good enough for landing, a second opportunity will be available about 90 minutes later. Lunney will consider Florida only for Wednesday’s landing attempts, with plenty of consumables on board to stay in space through Saturday, if necessary.
You can follow the event on NASA’s website in the Landing blog.
About the US space shuttle fleet
Currently there are 3 operational space shuttle aircrafts in the fleet of NASA: Atlantis, Endeavour and Discovery. Discovery is the oldest one. It first flew in 1984 and performed both research and International Space Station assembly missions. The shuttle planes were designed by Maxime Faget, who also designed Mercury, Gemini and Apollo spacecrafts. In total six such orbiters were built. First one – Enterprise – was built only for testing purposes. Challenger blew up in 1986, 73 seconds after launch. Columbia broke apart in 2003 during landing.
At launch, it consists of a rust-colored external tank (ET), two white, slender Solid Rocket Boosters (SRBs), and the orbiter, a winged spaceplane which is the space shuttle in the narrow sense. The tank and boosters are jettisoned during ascent; only the orbiter goes into orbit. The orbiter usually carries 5-7 crew members. During re-entry to the ground it glides and lands without the use of engines. Like most jet airliners, the shuttle is mainly constructed of conductive aluminium, which would normally shield and protect the internal systems. However, upon takeoff the shuttle sends out a long exhaust plume as it ascends, and this plume can trigger lightning by providing a current path to ground.
When the approach and landing phase begins, the orbiter is at a 10,000 ft (3,000 m) altitude, 7.5 miles (12 km) from the runway. The pilots apply aerodynamic braking to help slow down the vehicle. The orbiter’s speed is reduced from 424 mph (682 km/h) to approximately 215 mph (346 km/h), (compared to 160 mph (260 km/h) for a jet airliner), at touch-down.
Conditions permitting, the space shuttle will always land at Kennedy Space Center. However, if the conditions make landing there unfavorable, the shuttle can touch down at Edwards Air Force Base in California or at other sites around the world. A landing at Edwards means that the shuttle must be mated to the Shuttle Carrier Aircraft, and returned to Cape Canaveral, costing NASA an additional 1.7 million dollars.
Source: nasa.gov, wikipedia.org