This afternoon, SpaceX is planning to launch its newest Florida freight mission for NASA, which will send approximately 5000 pounds of supplies to the crew at the international space station. For this mission, the company uses a Dragon cargo capsule that has been in space twice before. If it succeeds, it is the first time that the same Dragon goes on a third space flight.
The Dragon's main storage compartment contains a number of interesting goodies and scientific experiments with which the crew can collaborate in the coming months. These include a printer designed to make 3D organ-like tissues in space, as well as an experiment to grow cells taken from patients with multiple sclerosis and Parkinson's disease.
The launch will also entail an important piece of hardware for the station itself. Hidden in the trunk of the Dragon – the pressureless cylindrical structure that runs on the back of the capsule during the flight – is a new dock for the ISS. Known as the International Docking Adapter, this will eventually be attached to a port on the outside of the ISS. The installation will create a new parking space for two future commercial spacecraft, both currently being developed by SpaceX and Boeing.
This docking adapter, made by Boeing, is actually the third of its kind. The first International Docking Adapter was destroyed in 2015, when the SpaceX Falcon 9 rocket carrying it to the station fell apart after taking off. A second docking adapter was launched in 2016 on another Falcon 9 and then installed on a port during a space walk. That adapter saw action for the first time in March when SpaceX & # 39; s new Crew Dragon capsule was automatically docked in port during a non-bolted test flight. Once this new dock is installed, SpaceX and Boeing have two parking options at the ISS, which offers more flexibility for future missions.
"We are really looking forward to getting this here," said Bill Spetch, deputy manager of the International Space Station Transportation Office, at a press conference. "It is an important piece of hardware for the future of ISS, because it forms the basis for the way in which we will work with Commercial Crew vehicles and our partners in the future."
Today's flight is one of the last cargo missions SpaceX will perform under its first supply contract with NASA. Under this agreement, SpaceX is charged with launching 20 freight missions to the space station, and this upcoming flight is the 18th launch of the company. Both the 19th and the 20th supply missions also fly Dragons during their third space flight, according to SpaceX.
SpaceX will continue to launch supplies for the ISS once the 20th mission is completed. NASA has awarded SpaceX a second contract, which entrusts the company with launching even more delivery missions until 2024. For those flights, SpaceX plans to switch to a new version of the Dragon Cargo Capsule, one very similar to SpaceX & # 39; s Crew Dragon that will soon run NASA astronauts to the station. Just like the Crew Dragon, the freight version can be automatically linked to the ISS. The current SpaceX freight capsules must be grabbed by the robotic arm of the station and then placed on the ISS. Soon all dragons can go to the station independently.
That future is still free for a few years. In the meantime, SpaceX's vision of hardware reuse is fully reflected in this mission. Not only has the Dragon cargo capsule flown twice (once in 2015 and once in 2017), but most of the Falcon 9 rocket on this flight also flew to space and back for a new cargo mission in May. For this launch, the rocket will attempt to hit one of SpaceX & # 39; s concrete runways in Cape Canaveral, Florida after takeoff. SpaceX has an almost perfect record for landings – except for one rocket that was accidentally dumped into the ocean.
Today's flight is scheduled for launch at 6:24 PM ET from SpaceX & # 39; s launch pad at Cape Canaveral Air Force Station. The company has an immediate launch window, so the rocket must take off on time or the mission must be delayed. It looks like this flight may not be taking place today – or even this week. There is only a 30 percent chance that will work together again this afternoon, and the odds are just as bad for tomorrow, the backup launch day. If SpaceX has to postpone this week, this flight is not possible until August at the earliest, due to other spaceships arriving in the coming weeks and leaving the ISS.
The launch is still ongoing and both NASA and SpaceX plan to provide live coverage. The NASA live stream starts at 6:00 PM on the agency's special TV channel, while the SpaceX live stream starts about 15 minutes before launch.