All about NASA’s giant rocket that will take astronauts to the moon and Mars – 6/14/2021 – science

NASA is developing a giant rocket called the Space Launch System (SLS) to take astronauts to the moon and eventually Mars. The SLS is the most powerful launcher built since 1960 and is due to hit the market at the end of 2021.

NASA plans to send a man and a woman to the lunar surface later this decade – it will be the first human landing on the natural satellite’s surface since Apollo 17 took off in 1972.

Astronauts have routinely traveled to the International Space Station (ISS) for 20 years, but the moon is almost a thousand times farther away than the ISS. To get astronauts there, you need a much more powerful rocket.

The SLS is the modern day equivalent of Saturn V, the large launch vehicle built during the Apollo spacecraft era. Like Saturn, it is divided into segments or stages that are stacked on top of each other. But the new rocket also contains space shuttle technology.

The first version of the SLS will be called Block 1. It will undergo a number of upgrades over the next several years to enable it to launch heavier payloads to targets beyond low-earth orbit.

SLS Block 1 will be 23 floors above the launch pad and is thus higher than the Statue of Liberty (93 m).

“It’s a really huge rocket. It’s just huge,” said John Shannon, vice president and program manager for SLS at Boeing, NASA’s prime contractor for the rocket’s production. “You just haven’t seen anything like this since Saturn V,” Shannon told the BBC in 2019.

The rocket will bring astronauts into NASA’s next generation of manned vehicles – Orion vehicles. The SLS will propel Orion at the speed required to leave near-earth orbit and travel to the moon.

This is how the rocket works

The SLS consists of a huge central stage flanked by two Solid Rocket Boosters (SRBs). The core houses two large storage tanks: one for liquid hydrogen, the fuel, and one for liquid oxygen, which enables the fuel to burn. Together they are called propellants.

At the base of the center stage are four RS-25 engines, the same ones that powered the former space shuttle carrier, which was retired in 2011.

When the engine chambers are fed with liquid hydrogen and oxygen and ignited, a chemical reaction begins that generates huge amounts of energy and steam. Steam emerges from the engine’s nozzles at a speed of 16,000 km / h and creates propulsion – the force that pushes the rocket upwards.

In addition to the power generated by the engine, the side rocket boosters also help the SRB to escape the massive gravity of the earth. These twin engines are 17 stories high and burn 6 tons of solid propellant per second. They are responsible for 75% of the total propulsion during the first two minutes of flight.

The most powerful missile ever?

If we take propulsion as a measure, the SLS will be the most powerful rocket of all time when it goes into space in 2021. Unit 1 SLS will generate 39.1 meganewtons of thrust (propulsion) at launch, 15% more than the Saturn V.

In the 1960s, the now-defunct Soviet Union (USSR) built a missile called the N1. Its first stage would produce 45.4 meganewtons of thrust. But all four test flights failed.

A future version of SLS – called Block 2 – should approach the drive levels of N1. But a vehicle called the Starship, developed by Elon Musk’s SpaceX company, can top both – with a thrust of 66.7 meganewtons. This spaceship is currently under development and there is no set date for its maiden flight.

How space shuttle technology was reused

The central stage of the SLS is based on the outer tank of the space shuttle, which is covered with foam. This tank provided fuel for three RS-25 engines in the rear of the shuttle orbiter. Solid rocket boosters perform pretty much the same function on both ships.

But SLS is very different. Due to the different voltage levels reached in the new rocket, some of the components and structures derived from the space shuttle have changed significantly.

An example is that the RS-25 engines on space shuttles were far from the SRBs and tilted upward. In the SLS, the engines, along with the SRBs, are exposed to significantly stronger vibrations. Therefore, every system in the complex SLS engine section had to be put through its paces to ensure that it could withstand the vibrations.

Why SLS was built

In February 2010, the Obama administration canceled George W. Bush’s difficult plan to return to the moon in 2020, called Constellation.

The news was badly received by workers in five southern states – Alabama, Florida, Louisiana, Mississippi, and Texas – where NASA’s manned space program created tens of thousands of jobs.

Some lawmakers were furious. At the time, Richard Shelby, a Republican senator from Alabama, said Congress would not “sit back and watch the ruthless abandonment of the manned space program.”

Legislators in the affected states then insisted on developing a single high-powered missile to replace the Constellation launchers that the White House had canceled.

The SLS design, based on NASA engineering studies, was introduced in 2011. After the rocket’s development began, delays and budget overruns gave ammunition to critics who believed NASA should be working with rockets operated by commercial vendors.

But without significant modifications, no existing engine has enough power to send the Orion spacecraft, astronauts and large payloads to the moon in one flight – as the SLS would.

A recent report said NASA will have spent more than $ 17 billion (R $ 87 billion) on SLS by the end of fiscal 2020.

But with the rocket’s development phase now complete and an evaluation program called Green Run successfully completed, the first SLS rocket is now in the Kennedy Space Center in Florida, preparing for its maiden flight in late 2021.

John Shannon, who has been in charge of the SLS at Boeing since 2015, said: “I believe that once the SLS is at full capacity there will be no need for another heavy vehicle like this one in the same generation for many years.”

Leave a Reply

Your email address will not be published. Required fields are marked *