SpaceX

The private launch contractor resupplying the ISS said a plan to recover the rocket's spent first stage at sea hit a snag.

The space firm will send a supply capsule into orbit, and then try a new way to recover the part of the rocket that carried it. If it works, the cost of going to space could be reduced dramatically.

By 2017, the two American companies are expected to take over a job that NASA has relied upon Russia to perform: shuttling astronauts to the International Space Station.