The three astronauts aboard the International Space Station usually have six months of food and water supplies, NASA says, but a failed resupply mission on the weekend has left them with only four months worth.

The crew has enough food and water to last them only until the end of October. A resupply mission on Friday is expected to extend that supply by one month.

The unmanned SpaceX rocket broke apart less than three minutes after liftoff from Cape Canaveral, Fla., on Sunday morning. The Falcon 9 rocket was carrying more than 2,300 kilograms of cargo.

The failure is the third unsuccessful cargo mission over the past eight months. A Russian cargo ship did not complete its mission in April, and an Orbital Sciences Corp. capsule was destroyed in a launch accident in October.

'Not even close' to bringing crew back

A three-person crew is living aboard the ISS:

Gennady Padalka, the Russian commander.

Scott Kelly, an American.

Mikhail Kornienko, a Russian.

Kelly and Kornienko launched in late March and have spent 93 days in space, while the commander recently broke the world record for most accumulated time in space, surpassing the 803-day mark this weekend.

"Certainly, if we didn't see any vehicles on the horizon today, we would be considering whether or not to fly the three crew that we have," NASA's manager of the ISS program, Mike Suffredini, said during a conference following the Falcon 9 failure.

NASA is always in the position, should they decide they do not have the means to support the crew aboard the ISS, to bring them home safely, he said.

"But, we're not even close to that kind of conversation today given the logistics we have on board."

The program was prepared to continue supporting the crew even if several planned resupply missions failed, he said.

"They've done a tremendous job balancing all the consumables on orbit," said William Gerstenmaier, NASA's associate administrator for human exploration and operations, at the same conference. The crew is "in good shape" for both food and water.

"The teams have really prepared for this event."

Resupply launch on Friday

When the timeframe for supplies narrows to 45 days worth of food and water, Suffredini said, NASA will start to make plans to bring the crew back to Earth.

Russia's Progress 60P cargo craft is scheduled to launch on Friday, and bring supplies and fuel to the ISS.

Suffredini said the Russians have loaded the spacecraft with food, water and other crew provisions. Despite losing the Falcon 9's cargo, he said he couldn't think of anything extra he would like to add to Progress's haul.

He projects the supplies on the Progress will add another month of food and water for the crew.

However, "a blow" to the team came from losing a multi-filtration bed replacement aboard the Falcon 9 that purifies water, said Gerstenmaier.

Recent measurements indicate that the multi-filtration beds and water processor aboard the ISS are starting to get full, Suffredini said. But, the ISS has quite a bit of processed water stored on board, he said, and it should last the crew as long as their food supply is expected to.

SpaceX is investigating the failure, which has been classified as a mishap, with oversight from the Federal Aviation Administration, which granted SpaceX a launch licence for the event.