The STS-121 mission has ended and the crew of space shuttle Discovery have returned home to Texas. STS-121 Commander Steven Lindsey, Pilot Mark Kelly, Mission Specialist Mike Fossum, and Mission Specialists Lisa Nowak, Stephanie Wilson and Piers Sellers were given a hero's welcome by hundreds of colleagues, friends, family and members of the public. In turn, the crew thanked those who made the flight successful.

Discovery flight commander Steven Lindsey recalls NASA's two major objectives. One is to complete the 'Return to Flight' test objectives and the other is to get up to the space station, prepare it for assembly, fix whatever's broken, and deliver critical supplies to the crew. Both objectives were achieved and Lindsey acknowledged the support of the mission control teams in Houston:

"Every single minute we were awake and every single minute we were asleep, they flew the mission with us. They were up there with us every day. We were talking to them all the time. I can't count the number of times during the mission that these teams made critical decisions that made the difference between succeeding on a timeline or failing on a timeline. And they just did a superb job."

Talk about long distance home delivery service! The International Space Station's (ISS) pantry is now well stocked with fresh food, equipment and other vital supplies after Discovery astronauts installed the Italian-built Leonardo cargo module at the orbital laboratory. Leonardo, a Multi-Purpose Logistics Module (MPLM), holds more than 5,000 pounds of the total 7,000 pounds of supplies launched toward the ISS aboard Discovery.

Additional items are being moved into the ISS from Discovery’s middeck and over the next week or so, all nine astronauts aboard the ISS will be busy with the intricately choreographed cargo transfer process. “We can’t really pull everything out of our logistics module and put it in the station because it would be so crowded we couldn’t move through it,” STS-121 commander Steven Lindsey. "It’s kind of a shell game where you have to make room for something before you pull something else out.”

Included among the thousands of pounds of cargo aboard Leonardo is a new Oxygen Generation System that will separate water into breathable oxygen and waste hydrogen once installed inside the Destiny laboratory. Together with the existing Russian-made Elektron currently aboard the ISS, the U.S. oxygen generator, the two systems will help support larger, six-person crews.

Leonardo also carried a Cycle Ergonometer with Vibration Isolation and Stabilization (CEVIS), a hi-tech exercise cycle so astronauts can maintain muscle strength during the long months of weightlessness. A Minus Eighty Laboratory Freezer for storing biological specimens for later transport back to Earth and a European Modular Cultivation System (EMCS) which would check plant growth under different stresses were part of the cargo. Shuttle and ISS astronauts are expected to begin retrieving the new freezer, oxygen generator and numerous other supplies inside Leonardo after opening its hatchway at 2:23 p.m. EDT (1823 GMT) today.

The International Space Station (ISS) became the happiest place on Earth, err, in space when the seven crew members of the Discovery came aboard. This was Mission No.1 accomplished for the the STS-121 spaceflight. Tony Ceccacci, lead shuttle flight director for the Discovery mission said the orbiter’s docking at the ISS marks the start of a spaceflight marathon for the shuttle’s crew.

Veteran space cowboy and Discovery’s STS-121 mission commander, Steven Lindsey, eased the 100-ton shuttle into a berth at the end of the ISS Destiny lab at 10:52 a.m. EDT (1452 GMT) today. Less than two hours later, Lindsey and his six STS-121 crewmates were exchanging handshakes and hugs with ISS Expedition 13 commander Pavel Vinogradov and flight engineer Jeffrey Williams.

Among the major achievements during the orbital rendezvous was Discovery’s orbital back flip executed while flying 600 feet below the ISS. During that time, Vinogradov and Williams took 350 still images later relayed down to Earth to be analyzed to determine the state of the Discovery’s heat shield.

The Discovery crew also oriented a thruster heater towards the Sun to keep it warm and made fine adjustments with the engine. Aside from those issues, Discovery’s STS-121 mission – and its crew – are sailing quietly along. “You know, it’s boring to us that it’s quiet, but that’s a good thing,” Ceccacci said. “That means everything is going well.”

On May 31, National Aeronautics and Space Administration (NASA) managers will brief the media about what's going on with the Space Shuttle Program and the next shuttle mission, designated as the STS-121. It would be happening at 3pm EDT and will be aired live on NASA Television and on the Web from the Kennedy Space Center in Florida.

Questions from the members of the media will be answered by Wayne Hale- Space Shuttle Program Manager, and Mike Leinbach- NASA Launch Director. If you want to be in the know about what's up with the Space Shuttle Program, you could click here and see how you can watch the media update.

If you do not have an inkling on just what STS-121 is, it is NASA's second shuttle test flight since the untimely 2003 demise of the space shuttle Columbia which killed all its crew members, including Kalpana Chawla- the first Indian-born woman and the second person of Indian origin to fly in space (Cosmonaut Rakesh Sharma was the first one), and Ilan Ramon - the first Israeli Astronaut.

The STS-121 would be under the capable hands of shuttle veteran, Steven Lindsey. This mission will be testing the shuttle fuel tank modifications, orbiter repair techniques, and then resupply the International Space Station during its mission starting from July 1 to July 19.

After the 2003 Columbia accident, NASA is back on track. The space shuttle Discovery has been placed at the launch pad at the Kennedy Space Station in preparation for its planned July 1 launch. Many are hoping this orbiter mission will push through.

The STS-121 mission is only NASA's second shuttle test flight since the 2003 space shuttle accident. The Discovery shuttle will be launching form Pad 39B of KSC and will be led by shuttle veteran Steven Lindsey. This mission will be testing the shuttle fuel tank modifications, orbiter repair techniques and then resupply the International Space Station during its July 1 to 19 run.

Discovery will be carrying with it the cargo pod dubbed Leonardo, spare space station parts and some other items. Tests will still be done to the shuttle before its planned launch.