After a Thursday attempt was delayed by lightning, a SpaceX Falcon 9 carrying scientific hardware to the International Space Station is scheduled for a second try at 5:07 p.m. Eastern today. There’s a significant chance weather will interfere again, though, with Air Force meteorologists putting the chances for acceptable conditions at Kennedy Space Center in eastern Florida at only 60%.
The Falcon 9 rocket will carry a Dragon capsule that will rendezvous with the ISS in orbit and deliver nearly 6,000 pounds worth of supplies. This will be SpaceX’s 11th resupply mission to the ISS, but the first to use a Dragon craft re-used from a previous mission. The Dragon currently on the launchpad at Kennedy Space Center first flew in SpaceX’s fourth resupply mission in September 2014. It is planned to stay at the ISS for a month during its current mission.
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A successful mission with this Dragon would add to the quickly-lengthening list of components that SpaceX has successfully reused or recovered in reusable condition, which now also includes both the first stage of the Falcon rocket and the nose cowling that protects payloads like the Dragon. Tesla CEO Elon Musk has said that SpaceX could re-use 100% of its major rocket components by 2018.
Re-using rockets and other launch elements is key to SpaceX’s existential mission to reduce the cost of space flight. Most current rocket models, including those from Arianespace, United Launch Alliance, and Russian rocket programs, are only used once, meaning each launch incurs huge material costs. Successful fulfillment of SpaceX’s reusability efforts could render other launch platforms financially uncompetitive.
However, SpaceX has faces serious challenges recently, including a launchpad explosion last September which may have put the company on fragile financial footing. Musk early this year said SpaceX would accelerate its launch schedule dramatically to make up for time lost following the explosion, but so far they’re slightly behind his goal pace of a launch every two to three weeks.