After a series of failed resupply missions, a Russian capsule loaded with crew provisions is expected to dock at the International Space Station early Sunday.
The unmanned rocket blasted off from the Baikonur Cosmodrome in Kazakhstan on Friday. It had more than three tons of food, fuel, water, oxygen and other supplies.
While such missions are fairly routine, past spacecraft resupply attempts have failed, making this one especially crucial.
In late June, an unmanned SpaceX rocket carrying a supply capsule exploded shortly after liftoff from Cape Canaveral, Florida.
It was carrying a spacesuit, water filtration equipment, crew provisions, food, water and student experiments. It was unclear what caused the rocket to fail, but a Federal Aviation Administration investigation is underway.
Failed missions
Three space station astronauts — two Russians and NASA’s Scott Kelly — had been awaiting SpaceX’s shipment.
There was another Russian rocket, Progress 59, which went out of control after launch in April and burned up on re-entry in May. It had crew clothing, spacewalk hardware, propellant, oxygen, water, spare parts, supplies and experiments.
But wait, there’s more.
In October, another rocket had to be destroyed when a problem developed after launch. It was carrying crew provisions and equipment as well.
Crew awaiting supplies
NASA says the three-person crew on the space station has enough supplies to last until October, even without the gear on the latest rocket.
“The space station crew is fine on orbit,” NASA’s William Gerstenmaier said. “They’ve done a tremendous job of balancing all the consumables on orbit. We’re in good shape from a food standpoint.”
However, he said, the crew will need to watch water levels. One of the most important items lost in the SpaceX explosion was a piece of equipment that filters water.
“Even without processed water, we have enough water supplies on orbit until late 2015,” NASA spokeswoman Stephanie Schierholz said.
In addition to Kelly, the current crew on the space station includes Russians Gennady Padalka and Mikhail Kornienko.
Kelly and Kornienko are taking part in what NASA describes as “The One-Year Crew.” They’re living on the space station about a year to explore the effects of long-term space flight on the human body.
Three more crew members are scheduled to go to the space station on a Russian spacecraft this month.
The space station
The station orbits about 248 miles (400 kilometers) above Earth. It circles the planet every 90 minutes.
Astronauts living there mostly conduct experiments, NASA said. It measures 357 feet and is larger than a six-bedroom house.
The latest rocket is expected to dock with the space station Sunday at 3:13 a.m. ET.