STS-135 Flight Day 4 is drawing to a close as the crews of the International Space Station and Atlantis prepare for bed at 6:29 p.m. EDT and 6:59 p.m., respectively.

They attached the Raffaello multi-purpose logistics module to the Earth-facing port of the station's Harmony node at 6:45 a.m., opened the hatch at 12:10 p.m. and began offloading 9,403 pounds of spare parts, equipment and supplies.

They also prepared for the mission's only spacewalk, which will be conducted by station crew members Mike Fossum and Ron Garan beginning at 8:44 a.m. EDT Tuesday.

earlier related report
STS-135: What if?
by Launchspace Staff
Bethesda MD (SPX) Jul 12 - Yesterday, at 11:07 a.m. EDT, Commander Chris Ferguson guided Space Shuttle Atlantis into Pressurized Mating Adapter #2 on the International Space Station's (ISS) Harmony node. The two spacecraft were flying at about 390 km, east of New Zealand, at the time they docked.

This was the 12th and final time Atlantis docked to the space station. It was the 46th shuttle docking to a space station, nine to the Russian Mir station and 37 to the ISS. Atlantis performed seven of the nine Mir dockings.

This was the 86th Space Shuttle rendezvous operation and the 164th "proximity operation" in the history of the Space Shuttle Program, where a shuttle conducted operations in close proximity to another spacecraft.

The shuttle and station crews opened the hatches and held the traditional welcome ceremony about two hours after docking. Atlantis' crew of Ferguson, Pilot Doug Hurley, and Mission Specialists Sandy Magnus and Rex Walheim joined Expedition 28 Commander Andrey Borisenko and Flight Engineers Alexander Samokutyaev and Sergei Volkov of Russia, Satoshi Furukawa from Japan, and NASA's Ron Garan and Mike Fossum.

The combined crew of 10 will spend more than a week of docked operations, transferring vital supplies and equipment to sustain station operations once the last shuttle is retired. If all goes well Atlantis will depart ISS and return to Earth.

If Atlantis is deemed unsafe to return to Earth, NASA has developed an emergency plan to ensure that the shuttle's four astronauts are not trapped in space.

In the unlikely event that Atlantis cannot return to Earth as planned, the crew will remain on the station until they can be rescued by Russian Soyuz spacecraft. The odds of this happening are very low, but NASA is required to prepare for all kinds of emergency situations, regardless of how remote they may be.

Russia launches an average of four Soyuz spacecraft a year to ISS. Each Soyuz typically carries three crew members in order to constantly replenish the station's crew complement of six.

Thus, if Atlantis is deemed unsafe for re-entry, the four shuttle astronauts will remain on the station and wait for the normal rotation of Soyuz vehicles to come up one by one.

NASA statisticians have estimated the odds of this scenario to be 1 in 560. Should it however happen, the last Atlantis astronaut would not get home in less than about 340 days. In other words, the STS-135 flight plan calls for a 12-day trip, but it could last for almost a year for at least one astronaut. This is beginning to sound like some of my bad trips.

Tweet

Related Links station at NASA Shuttle at NASA Shuttle at NASA Watch NASA TV via Space.TV Space Shuttle News at Space-Travel.Com