Washington, April 20: Space shuttle Discovery touched down at the Kennedy Space Centre in Florida on Tuesday, completing a 15-day mission to the International Space Station (ISS).
The landing at 9:08 a.m. (1838 IST) was about 90 minutes later than planned because of fog and rain at Kennedy. US space agency NASA had to delay its planned Monday landing because of bad weather.
Discovery undocked Saturday from the ISS after installing a new ammonia tank and delivering experiments and other gear. It delivered more than 6 tonnes of gear, including Earth observation equipment and exercise equipment to prevent and study astronaut muscle atrophy.
The shuttle also arrived home with nearly 2 tonnes of used equipment and completed experiments stored inside the Italian-made Leonardo module.
The Discovery astronauts completed three spacewalks to install the ammonia tank to the station’s cooling system. But a problem with a stuck valve, which was needed to get the tank operating, caused problems and NASA briefly considered adding a fourth spacewalk to fix it.
The space agency eventually decided the tank could operate as it is temporary and the problem could be solved on a later mission.
The mission for the first time saw four women and two Japanese astronauts aboard the ISS with the combined crews of Discovery and ISS.
NASA is scheduled to retire the ageing space shuttle fleet later this year after just three remaining missions. The next shuttle flight is scheduled for mid-May. Discovery is slated to complete the final flight in September.
The long-standing decision to retire the fleet will leave the US reliant on Russian Soyuz spacecraft to lift astronauts into space. President Barack Obama hopes to use commercial providers who can offer “space taxis” to bring astronauts to the ISS within
several years, freeing NASA to focus on long-term goals such as reaching Mars.
—Agencies