Since the ending of the space shuttle program in 2011, NASA has turned to private companies to begin delivering cargo – and eventually astronauts – to the International Space Station. California-based SpaceX and D.C.-based Orbital Sciences have collectively received $3.5 billion from the space agency to send supplies to the ISS. Today, Orbital Sciences successfully conducted a test launch of their Antares rocket, and the company hopes to dock with the ISS this summer.

Though the first two launch attempts this week were scratched due to an equipment malfunction and excessive winds at Virginia’s Wallops Island, Antares’s payload successfully separated from the rocket after reaching orbit. This summer, an Orbital Science rocket will carry a Cygnus cargo ship to attempt to dock with the ISS, and while it’s up there, it’ll deliver about 1,600 pounds of clothing, food, and extra equipment. The Cygnus cargo ship won’t return to Earth, however; like the cargo ships of Europe, Russia, and Japan, it will be filled with trash from the ISS to be incinerated on re-entry.

SpaceX made its test launch last May, complete with a similar delivery of batteries, clothing, and food, and the company is working on tweaking its Dragon capsules to deliver astronauts to the ISS. Currently, US astronauts have to rocketpool with the Russian cosmonauts to get up to the space station.

If all goes well, SpaceX will make 12 restocking missions and Orbital Sciences eight under their respective contracts.  The astronaut-delivering contract will have even more competitors, so keep on the lookout for those as well.