FILE - This May 23, 2010 image provided by NASA shows the International Space Station with the Earth in the background made from the space shuttle Atlantis after undocking. On Wednesday, Jan. 8, 2014, NASA said the White House was poised to announce an extension of the space station's lifetime until at least 2024. The previous end-of-life date was 2020. (AP Photo/NASA)
CAPE CANAVERAL, Fla. (AP) SpaceX is back on the launch pad in hopes of making a critical delivery to the International Space Station.
Liftoff is scheduled for 3:25 p.m. Friday. But stormy weather may force another delay.
NASA's commercial supplier was foiled by a leaky rocket valve during Monday's launch attempt. The valve has been replaced.
The unmanned Dragon cargo ship contains 2 1/2 tons of station supplies, including material for urgent computer repairs. A backup computer failed outside the space station last Friday. Astronauts will conduct a spacewalk to replace the computer in the next few days.
NASA says the material on the Dragon is desirable for the repair job, but not essential. Much-needed food is also aboard, along with a new spacesuit and spacesuit replacement parts.