CAPE CANAVERAL, FL - Late Sunday night (technically early Monday morning) SpaceX will launch its ninth Commercial Resupply Services (CRS) mission to the International Space Station (ISS), carrying a docking adapter critical to the future of America's manned space program.
The International Docking Adapter (IDA) being ferried to the station aboard SpaceX's Dragon cargo vessel will be permanently attached to the ISS; mated to the same docking port used by the space shuttles.
Once outfitted to the station, the IDA will make it possible for future manned spacecraft to dock and interface with the orbital laboratory. Most notably, SpaceX's Crew Dragon and Boeing's CST-100 Starliner - both human-rated capsules under development through NASA's Commercial Crew Program (CCP) - will rely completely on the IDA for station access.
IDA-2, the docking adapter currently awaiting launch inside Dragon's trunk, is the second adapter built by manufacturer Boeing. The first, IDA-1, was lost in June 2015, when the CRS-7 Falcon 9 launch vehicle exploded 139 seconds after liftoff.
A third adapter, a replacement for IDA-1, is slated to launch in March, 2017. Engineers at Boeing and NASA, efficient as they are, are ahead of their production schedule for IDA-3. CCP Partner Manager Jon Cowart speculates that, given the ability to do so, IDA-3 could launch sooner.
With occasional overlaps expected between the arrivals and departures of the Crew Dragon and Starliner, any failure of the IDA in either its delivery or functionality would result in significant dynamic shifts in NASA’s future CCP mission plans.
Assuming all goes according to plan, the IDAs will be mated to the ISS's two Pressurized Mating Adapters (PMA), both of which will be attached to the Harmony module. The new adapters will provide a more sophisticated, technologically advanced interface between spacecraft and the ISS. They feature upgraded lasers and sensors that enable digital communication between spacecraft and station during automated alignment and docking procedures. Once docked, spacecraft will then be able to draw power and share other resources with the ISS.
SpaceX’s Dragon capsule is scheduled to rendezvous with the International Space Station July 20, with a capture by Canadarm2 set for 9:45am. As the crew unloads Dragon's cargo in the coming days, the station’s robotic arm will remove the the docking adapter from Dragon’s trunk and place it about 30 cm from the PMA. During an EVA, astronauts will then manually connect the IDA to the PMA, readying it for use.
This will be SpaceX’s ninth Commercial Resupply Services mission, and will launch Monday, July 18, at 12:45am. Watch NASA’s live coverage on NASA TV starting at 11:30pm Sunday night.
Live coverage of the rendezvous and capture of the Dragon capsule begins July 20, at 5:30am.