The International Space Station's Expedition 40 crew tackled physics and medical research Tuesday, as a new Russian resupply spacecraft rolled out for Wednesday's launch to the orbiting complex. Meanwhile, flight controllers are tracking a possible conjunction with a piece of space debris that could come into the neighborhood of the station on Wednesday morning

The ISS Progress 56 cargo craft rolled out on a railcar to the launch pad at the Baikonur Cosmodrome in Kazakhstan early Tuesday morning for final preparations for liftoff. The Progress, loaded with about 5,700 pounds of food, fuel and supplies for the six-person Expedition 40 crew, will launch Wednesday at 5:44 p.m. EDT (3:44 a.m. Thursday, Baikonur time) on a 4-orbit, 6-hour fast track rendezvous to dock with the station's Pirs docking compartment at 11:30 p.m.

Live NASA Television coverage of the Progress launch begins at 5:30 p.m. and returns at 11 p.m. for docking coverage.

Pirs was vacated late Monday with the undocking of the ISS Progress 55 cargo craft, which separated from the station at 5:44 p.m. Progress 55 is now a safe distance from the complex for a series of engineering tests prior to being sent to a destructive re-entry over the Pacific Ocean on July 31.

Aboard the orbiting complex, Commander Steve Swanson began the workday with another eye exam for the Ocular Health study.

NASA recently identified that some astronauts experience changes in their vision, which might be related to effects of microgravity on the cardiovascular system. Researchers are working to understand and prevent these changes in astronauts.

With guidance from the Ocular Health team on the ground, Flight Engineer Alexander Gerst examined Swanson's eyes using optical coherence tomography equipment.

Afterward, Swanson conducted an ultrasound scan of his right thigh and calf for the Sprint experiment, which measures the effectiveness of high-intensity, low-volume exercise training in minimizing the loss of muscle mass and bone density that occurs during spaceflight.

Station crew members currently work out around 2 0.5-hours every day, and the Sprint team is looking into ways to reduce that total exercise time while maintaining crew fitness. Gerst assisted the commander with this Sprint session.

Then it was Gerst's turn to provide data for the Ocular Health study, as Swanson conducted an optical coherence tomography exam on the European Space Agency astronaut's eyes.

Flight Engineer Reid Wiseman began his day removing sensors and an armband monitor that had tracked his body's core temperature over a 36-hour period for the Circadian Rhythms study. Because the station orbits the Earth every 92 minutes and experiences 16 sunrises and sunsets every day, the astronauts do not have the same day/night cues that people have on Earth.

Results from this investigation will provide insights into the adaptations of the human autonomic nervous system in space and will help optimize crew schedules and workplace illumination.

Wiseman moved on to setting up the Burning And Suppression of Solids experiment, or BASS, for another round of combustion studies in the Microgravity Science Glovebox.

BASS is investigating the hypothesis that some materials may actually become more flammable in space, and the results from BASS will help screen materials for their use aboard future spacecraft. The research also provides scientists with improved computational models that will aid in the design of fire detection and suppression systems both in space and here on Earth.

Following a break for lunch, Wiseman photographed some slow growth experiment samples from the Binary Colloidal Alloy Test, or BCAT.

Swanson then removed and stowed the samples so the next set of BCAT samples could be processed. Results from this ongoing investigation of colloids - mixtures of small particles distributed throughout a liquid - will help materials scientists to develop new consumer products with unique properties and longer shelf lives.

Afterward, Swanson and Wiseman tagged up for a conference call with flight controllers on the ground to discuss the timeline for a spacewalk the two NASA astronauts will conduct in August.

As Wiseman wrapped up his work with BASS, Swanson and Gerst completed another set of Ocular Health exams, using a fundoscope to take detailed imagery of each other's eyes.

On the Russian side of the complex, Flight Engineer Max Suraev inspected windows in Pirs and the Zvezda service module. He also inspected and cleaned several laptop computers and recharged the satellite phone in the Soyuz TMA-13 spacecraft docked to the Rassvet Mini-Research Module-1.

Flight Engineer Alexander Skvortsov recharged the satellite phone in the Soyuz TMA-12 before moving onto the Virtual experiment, a study of the vestibular system's adjustment to weightlessness. Skvortsov also downloaded data from the Identification experiment, which tracks the dynamic loads on the station during events such as dockings or reboosts.

The third Russian cosmonaut aboard the station, Flight Engineer Oleg Artemyev, spent much of his morning replacing flow meters components in the Vozdukh atmosphere purification system. He later joined Skvortsov for some maintenance work on a communications panel.

Artemyev rounded out his workday setting up a thermostat for the Kaskad cell cultivation experiment. He also participated in the Vzaimodeystviye (Interactions) experiment, which studies the impacts of personal, cultural and national differences among crew members.

Meanwhile back on Earth, flight controllers are tracking a possible conjunction with a fragment of a Russian Breeze-M upper stage rocket body that could come into the neighborhood of the station on Wednesday morning. Discussions are being conducted with Russian ballistics officials on the best approach for a debris avoidance maneuver, should one be required.

The most likely option, if necessary, would be a slight retrograde burn (deboost) for the station that would provide adequate distance from the debris and still preserve the trajectory for the 4-orbit rendezvous of Progress 56.

As of Tuesday morning, the radial miss distance between the object and the station is calculated to be about 2/10 of a mile with an overall miss distance of some 19 miles. No final decision on the maneuver is expected until late Tuesday or early Wednesday, and there is no risk to the crew or operations on the station.

At Kourou, French Guiana, technicians are completing tests on the attitude control system in the third stage of the Arianespace Ariane 5 rocket that will launch the European Space Agency's fifth and final Automated Transfer Vehicle (ATV-5). Arianespace and ESA are working toward establishing a firm launch date, with launch likely to take place early next week. The ATV-5, named the "Georges Lemaitre" in honor of the Belgian physicist and astronomer, is slated to dock to Zvezda on August 12.