The biggest part of the biggest part of the biggest rocket is almost complete.
Catch all that?
The biggest rocket in the world is going to be NASA’s Space Launch System, or SLS. The biggest part of the rocket is the core stage. And the biggest part of the core stage is almost completed – it’s the liquid hydrogen tank. The photo below shows the liquid hydrogen tank and liquid oxygen tank, both parts of the core stage.
Image Credit: NASA/MSFC/Kevin O’brien
The main components of the core stage are being manufactured at NASA’s Michoud Assembly Facility.
More than 130 feet long and 27.5 feet in diameter, the liquid hydrogen stage just needs a final dome to be added to the end of it. Take a look inside:
Image Credit: NASA/Michoud/Steven Seipel
The silver structure in the photo is the tank, while the blue is the tool that welded it. It’s the biggest robotic welding tool in the world. It will also be used to weld on the final dome piece.
Why does it look like there are ridges on the inside of the tank?
The cylindrical barrels are made with square patterns that have stiffening ribs in them. This enables the tank walls to be both light and strong. It may hold liquid, but it’s solid.
The liquid hydrogen tank discussed here is the qualification tank and will be tested at Marshall Space Flight Center. It will experience forces that simulate launch and ascent. This tank will only be used for testing, not the actual flight.
SLS will blast off in 2018 carrying the Orion crew vehicle and small satellites called cubesats. The rocket design is evolvable, and during the following launch, the exploration upper stage will be more powerful. Throughout the different configurations of the rocket, the core stage and the four engines powering it will remain the same. Coalition founding members Boeing and Aerojet Rocketdyne are the prime contractors for the core stage and engines, respectively.
Learn more about the rocket and the exciting missions it will enable at NASA.gov.