Nasa has completed the deployment of two booster rockets that will help propel its giant, next-generation launch system – the SLS.
The SLS, or Space Launch System, is the rocket that will bring astronauts back to the moon under the American Artemis project.
Over the course of a few months, workers from the Kennedy Space Center in Florida stacked the ten segments of the booster rockets vertically.
When SLS is operational, it will be the most powerful rocket in the world.
It can deliver up to 8.8 million pounds of propulsion, making it 15% more powerful than the Saturn V rocket that increases Apollo lunar transmissions.
The SLS consists of a large core stage with four powerful engines at the base and the two solid rocket amplifiers (SRBs) on either side.
The two completed SRBs at Kennedy Space Center will fly after the first launch of the SLS – known as Artemis 1 – planned for the end of 2021.
Each identical amplifier is divided into five segments known by large rocket pieces as the front and rear.
The SRBs are stacked on a structure called the mobile launcher, which will support the testing, completion and maintenance of the SLS, and can also transfer it to the launch site at the Kennedy Space Center.
The amplifiers, similar to those that helped launch the now-retired spacecraft, will provide 75% of the total propulsion at the lift.
On Twitter, Charles Precourt, vice president of propulsion systems at Northrop Grumman – which manufactures the SRBs – said it was ‘exciting to see a full stack of boosters’.
Engineers from Nasa’s Exploration Ground Systems team positioned the first segment on November 21, 2020, and continued the process until the final nose meeting on March 2 this year.
“The stack of sturdy rocket amplifiers is a major milestone,” said Cliff Lanham, senior manager of vehicle operations. “This means that the rocket is mounted on the mobile launcher and we are in the final phase of a long journey – to start Artemis 1.”
The SLS has the necessary thrust to propel Nasa’s next-generation crew vehicle, the Orion, to the moon without having to dock at Earth with a separate propulsion stage.
America returns to the moon under the Artemis program (named after Apollo’s sister in Greek mythology). The project was started under Donald Trump’s presidency; but in February, Biden’s government backed the lunar eclipse.
The Trump White House has set an aggressive target date of 2024 for the US space agency to carry out the first human landing on the Moon since 1972. However, the Biden government made no mention of this timeline, leading to speculation that the date was slipping.
The last major piece of the SLS waiting to be built into the mobile launcher is the orange core stage currently being evaluated at Nasa’s Stennis Space Center near Bay St Louis, Mississippi.
Nasa plans to conduct a “hotfire” test of the core by mid-March, which involves lighting all four engines. Engineers intend to fire them for the full eight minutes it takes before the SLS reaches space.
During the first attempt at an arson in January, a problem with the core stage hydraulics caused the test to end after only a minute.
The first flight of the SLS is currently scheduled for the end of 2021. On this, the rocket will launch an unmanned Orion spacecraft on a trip to Moon to do a full evaluation of both vehicles.
The compounds that connect each segment of the solid rocket amplifiers have a limited lifespan of 12 months. The stacking of the boosters means the clock is already ticking to start – although engineers have said there may be ways to extend the certification period.
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