Last space shuttle flight has packed schedule

Miami Herald: Last space shuttle flight has packed schedule
On the surface, the final mission of the space shuttle appears straightforward: a supply run to the International Space Station. But when is rocket science ever simple?

Apart from delivering about 8,000 pounds of food, clothing and spare parts to the six astronauts currently onboard the ISS, space shuttle Atlantis — which blasted off from Florida’s Kennedy Space Center Friday, marking the end of the 30-year space shuttle program — will also carry experiments in the fields of robotics, life-science and astrobiology.

“The main goal is to set the ISS up for continued operations through the end of 2012,” said Kwatsi Alibaruho,the lead space shuttle director for the mission, in a news conference at Houston’s Johnson Space Center the week before the planned blast-off.

One of the biggest experiments onboard will be the Robotic Refueling Mission (RRM) which will test the ability to refuel a satellite in space. Once satellites run out of fuel, they are discarded, said Benjamin Reed, deputy project manager of the RRM. This technology could be used to service hundreds of communications satellites that currently end up as space junk.

A Canadian Space Agency robot attached to the space station will use the tools provided by the RRM to practice transferring fuel between two components, Alibaruho said. A fuel-like liquid will be used for testing purposes.

Another experiment will study a natural phenomenon that could be used to purify water in space. The process, called “forward osmosis” occurs when water diffuses from an area of higher concentration to one of lower concentration, through a semi-permeable membrane. It’s what happens when you soak dried raisins or chickpeas in water and they swell up in a few hours.

Scientists will determine whether forward osmosis occurs at a different rate in space than it does on earth, said Spencer Woodward, project manager at Kennedy Space Center.

The machines that currently purify water are bulky, expensive and sometimes run into problems, Woodward said. The new process would use bags that are cheap, lightweight and small, which is convenient for space travel.

“We can use these on the ISS to save time and money,” said Woodward.

Another part of the mission will focus on retrieval of a defunct ammonia pump from the space station to learn why it failed. That will require a 6 ½ hour spacewalk by astronauts Michael Fossum and Ron Garan, who will deliver the pump to Atlantis and set up the robotic refueling experiment.

The astronauts themselves will also be the subjects of experiments on this final mission. An ultrasound machine will be onboard “to study the effects of microgravity on an astronaut’s physiology,” said Chris Edelen, lead flight director for the mission. Bone loss and a diminished immune system are common effects that astronauts experience in the absence of gravity.

Atlantis’ crew of four includes commander Christopher Ferguson, pilot Doug Hurley and mission specialists Sandra Magnus and Rex Walheim, all experienced astronauts. The mission lasts 12 days, though it could stretch an extra day if necessary, said Alibaruho.

The crew had mixed emotions at a news conference a week before the flight, as they tried to balance the importance of the final mission with the enthusiasm to get going.

“We have an event-filled, packed mission that we have to get through before we celebrate the 30-year run of the space shuttle,” Ferguson said.

The end of the shuttle, though, is like mourning the loss of a friend, he added.

“I say that every American taxpayer should go see a space shuttle launch, because after it, they’re different,” Ferguson said. “They get it.”