NASA named SpaceX and Boeing as its two top picks for the Commercial Crew Program back in 2012. That gave the two access to most of the agency's money earmarked for the project, though Boeing received almost twice the funding its rival got. Despite getting a smaller cut of the funding, SpaceX and its Crew Dragon vehicle could start ferrying astronauts to the ISS first, because Boeing is reportedly grappling with delays.

If you want to watch Rubins' first spacewalk and the dock's installation, make sure to fire up NASA TV on Friday, August 19th. The livestream will go online as early as 6:30AM Eastern, but the spacewalk itself isn't scheduled to start until 8:05AM.