Europe's cargo ship could stay at station a little longer
BY STEPHEN CLARK
Posted: April 30, 2008
A team of earthbound engineers and space fliers is methodically completing a checklist of cargo transfers and tests on the Jules Verne space station resupply ship, while European officials await word on whether the craft's stay at the complex could be extended by a month or more.
The station astronauts have moved a few items from Jules Verne, but there is no formal plan for unpacking most of the dry cargo, according to Bob Chesson, head of the European Space Agency's human spaceflight and exploration operations.
Jules Verne, the first in a series of five European Automated Transfer Vehicles built to ferry cargo to the station, hauled more than 2,500 pounds of dry cargo to the complex. The supplies included 1,100 pounds of food, 300 pounds of hardware for ESA's Columbus laboratory module, and 176 pounds of fresh clothing, according to European officials.
The ATV's fuel tanks also contain about 5,000 pounds of propellant set aside to raise the station's altitude and provide attitude control when the outpost's wheel-like gyroscopes are down.
Jules Verne's 28 thrusters took control of the station early April 5 to test their ability to manage the orientation of the 600,000-pound complex. The ATV's thrusters provided operational attitude control for the undocking of a Russian Progress freighter April 7 and the arrival of the Expedition 17 crew aboard a Soyuz spacecraft April 10, Chesson said.
The station crew manually turned valves to begin transferring 46 pounds of pure oxygen into the outpost's atmosphere April 14. The ATV has the ability to deliver oxygen and nitrogen in pressurized gas tanks, but Jules Verne was only loaded with oxygen.
Ground controllers conducted a test of Jules Verne's propulsion system April 21 to verify it was ready for a lengthy engine firing to raise the station's orbit. After reviewing the test results, officials approved a plan to use two of the ship's main engines in a 12-minute burn to boost the altitude of the complex, setting up for the arrival of the shuttle Discovery on a construction mission in early June.
The maneuver accelerated the outpost's blistering velocity by just six miles per hour, but enough to raise the station's orbit by an average of about 2.8 miles, according to a European Space Agency statement.
Three more re-boosts are scheduled for June 12, July 8 and August 6 to further refine the station's orbit.
Another 1,900 pounds of propellant will begin flowing into the Zvezda service module in late June, Chesson said.
The fuel will be used for Zvezda's own control jets, used when a visiting spacecraft is unable to steer the complex.
Jules Verne also transported nearly 600 pounds of water to the station. The fresh water, which will be used for drinking, cleaning and food rehydration, will be pumped into tanks inside Zvezda in the next few months, although the schedule for the transfer is still under review, Chesson said.
"We have already taken (water) samples and they have been analyzed and found to be good quality," Chesson said.
Currently slated to depart the station around August 10, Jules Verne could stay at the complex for an extra month if the project's international partners agree to revamp the schedule for a series of visiting missions later this year.
A Progress cargo ship, called Progress 30P in the station assembly sequence, is scheduled to dock to the same port Jules Verne occupies around August 14. In that case, the ATV would have to leave the station by mid-August, according to senior officials.
But Russia is considering postponing the Progress 30P mission until after the October launch of a piloted Soyuz spacecraft with the station's Expedition 18 crew. That decision would allow Jules Verne to remain docked to the complex through much of September, a senior manager told Spaceflight Now.
Officials expect to decide whether to delay the Progress mission in the next few weeks.