Russian resupply ship docks at International Space StationJuly 4, 2010 in Astronomy & Space / Space Exploration
An unmanned Russian supply vessel docked Sunday without trouble at the International Space Station, two days after a technical glitch forced a similar maneuver to be aborted.
Space officials said they managed to avoid the radio signal problems that forced them to abandon last week's docking of the Progress M-06M cargo ship, launched on June 30, is carrying 2.6 tonnes of fuel, food and water for the three Russia and three US astronauts on the station.
"At 20:17 pm Moscow time (16H17 GMT), the 'Progress M-06M' docked at the 'Star' module of the ISS," the Russian Mission Control Centre said in an Internet statement.
An attempted docking on Friday was aborted when a radio link with the ISS was lost about 25 minutes before the planned rendezvous.
Sunday's successful docking was done automatically under the supervision of experts in Moscow and the ISS team, it said, without using the radio link.
Progress launched from the Baikonur Cosmodrome in Kazakhstan on June 30.
It is the 40th Russian cargo vessel to dock at the station, the centre said.
In contrast to the troubles that plagued the first rendezvous attempt, Sunday's second try "was executed flawlessly," the US space agency NASA said on its website.
The space ship's failure to dock last week after flying past the ISS was notable largely because it was rare mishap in a space programme which usually strives for and achieves pinpoint accuracy.
During the mishap "in the beginning everything was normal, then the automatic (docking) mode failed, and later the station's crew could not dock the vessel in manual mode," a Russian space centre spokesman told the Itar-Tass news agency.
The automatic docking system also failed during the last Progress supply ship docking in May although the process was successfully carried out manually.
The ISS, which orbits 350 kilometres (220 miles) above Earth, is a sophisticated platform for scientific experiments, helping test the effects of long-term space travel on humans, a must for any trip to distant Mars.
Progress is carrying 1,918 pounds (862 kilos) of propellant, 110 pounds (50 kilos) of oxygen, 220 pounds (100 kilos) of water and 2,667 pounds (1,210 kilos) of experiment equipment, spare parts and other supplies to the station.
The rendezvous occurred 220 miles (350 kilometers) above Earth as both the ISS and resupply ship flew over the point where the borders of China, Kazakhstan, Mongolia and Russia intersect.
Progress is similar in appearance and design elements to the Russian Soyuz spacecraft, which brings crew members to the station, serves as a lifeboat while they are there and returns them to Earth. And unlike Soyuz, Progress has a refuelling module and a cargo module.
(c) 2010 AFP
"Russian resupply ship docks at International Space Station" July 4, 2010 https://phys.org/news/2010-07-russian-resupply-ship-docks-international.html