NASA has been developing a giant rocket called the Space Launch System (SLS) to launch astronauts to the moon and eventually to Mars. SLS will debut in November 2021
NASA plans to send men and women to the moon’s surface by 2024. This is the first human landing since Apollo 17 in 1972.
For the past 20 years, astronauts have been making routine trips to and from the International Space Station (ISS).
However, the moon is nearly a thousand times larger than the International Space Station. To keep the astronauts there, a giant rocket is needed.
SLS is the modern equivalent of Saturn V, which is a large launcher built during the Apollo era. Like Saturn, it is divided into multiple parts or stages, stacked on top of each other. But the rocket also uses space shuttle technology.
The first version of SLS will be called Block1. It will undergo a series of upgrades in the next few years so that heavier payloads can be launched to destinations beyond low earth orbit.
The first SLS will stand 23 stories above the launch pad, higher than the Statue of Liberty.
John Shannon, vice president and project manager of the rocket general contractor Boeing SLS, said: “This is indeed a huge rocket. Its size is jaw-dropping.” He told BBC News in 2019: “When When you saw SLS put together, you have never seen anything like this since Saturn V.”
The rocket will be launched at the astronauts in the Orion, NASA’s next-generation crew vehicle, so that it will rise to the speed required to leave the low Earth orbit and enter the moon.
How the rocket works
The SLS consists of a huge core stage flanked by two solid rocket boosters (SRB). There are two large storage tanks in the core: one is used to store liquid hydrogen as fuel, and the other is used to store liquid oxygen, an “oxidant” that burns the fuel.
Together these are called propellants.
The core stage is based on four RS-25 engines, which power a space shuttle like a space shuttle, and were retired in 2011.
When liquid hydrogen and oxygen are fed into the engine room and ignited by sparks, the chemical reaction produces a lot of energy and steam.
Steam is ejected from the nozzle of the engine at a speed of 16,000 km/h (10,000 mph), producing thrust-the force that propels the rocket through the air.
SRB provides additional power for the rocket to escape the clutch of gravity. These dual boosters are more than 17 layers high and burn six tons of solid propellant per second. They provide 75% of total thrust during the first two minutes of flight.
The most powerful rocket ever?
If we use thrust as a yardstick, SLS will become the most powerful rocket ever when it flies into space in 2021. Block 1 SLS will generate 8.8 million pounds (39.1 meganewtons) of thrust when launched, which is 15% higher than that of Saturn V. .
In the 1960s, the Soviet Union made a rocket named N1 to reach the moon. Its first stage can generate 10.2 million pounds (45.4 meganewtons) of thrust. But all four test flights ended in failure.
The future version of SLS-called Block 2 cargo-should approach the thrust level of N1. But a vehicle called “Starship” developed by Elon Musk’s SpaceX company should be able to surpass both at the same time-generating up to 15 million pounds (66.7 trillion Newtons) of thrust . The interstellar spacecraft is currently under development, although there is no exact date for the first flight.
Number of SLS
Rocket will stand 98m (322 feet) The initial configuration or the first block configuration is higher
Block 1 SLS can be sent 27 metric tons (59,500 pounds) Entering lunar orbit-equivalent to 11 large off-road vehicles (SUV)
The future version of SLS is called Block 2 Cargo and will launch 46 metric tons (101,400 lb) To the moon. That is 18 large SUVs.
SLS will produce 8.8 million pounds (39.1 trillion Newtons) Thrust for 1 seat configuration
Four The RS-25 engine is the foundation of the core stage.They are the same as used in the space shuttle
How to reuse space shuttle technology
The core stage of SLS is based on the outer fuel tank covered by the space shuttle’s foam. The tank provides propellant to the three RS-25 engines at the rear of the space shuttle orbiter. The role of solid rocket boosters in the two vehicles is roughly the same.
But SLS is a completely different beast. Due to the different pressure levels exerted by the SLS on the space shuttle, many parts and structures produced by the space shuttle have undergone major design changes.
As an example of these different pressures, in the space shuttle, the RS-25 engine is tilted away from the solid rocket booster. Moving them next to the SRB will make them more shaken. Therefore, each system in the complex SLS engine part must undergo rigorous testing to ensure that it can withstand vibration.
Why establish SLS
In February 2010, the Obama administration cancelled the constellation plan-George W Bush plans to return to the moon in 2020. This is a heavy blow to workers in five southern states (Alabama, Florida, Louisiana, Mississippi, and Texas). The spacecraft of the National Aeronautics and Space Administration (NASA) funded Thousands of jobs.
Some legislators on Capitol Hill were irritated. Republican Senator Richard Shelby from Alabama said that Congress will not “sit and ignore reasonable principles, a reliable track record, a steady path to success, and the impact of our human space program. Destruction”.
As a compromise, lawmakers in the affected country insisted on using only one super-heavy rocket to replace the constellation launcher cancelled by President Obama.
The design of SLS is based on the technical research of NASA and was released in 2011. After the work started, delays and cost overruns caused critics of ammunition to believe that NASA should rely on rockets operated by commercial providers.
However, without major modifications, the existing boosters will not have enough power to transport Orion, astronauts and large cargo to the moon at once. Currently only SLS has this function.
A recent surveillance report stated that by the end of fiscal year 2020, NASA will spend more than $17 billion on SLS.
However, with the end of the rocket’s development phase, eight successful “green operations” tests conducted in the core phase will clear the way for launch in 2021.
John Shannon, who has been the head of Boeing’s SLS since 2015, explained: “I suspect that once SLS enters the ranks of the country, there will be no need for another heavy vehicle like this for many years. So it is indeed a rare opportunity. Opportunity.”
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