“Watching for the first time four RS-25 engines ignite at the same time in the core stage is an important milestone for the SLS space rocket.”
At 5:00 p.m. on January 16, 2021, NASA successfully tested the 65-meter-long SLS (Space Launch System) booster core. The rocket’s four Aerojet Rocketdyne RS-25 engines ignited for about eight minutes, generating 1.6 million pounds of thrust and consuming 700,000 gallons of propellant on a test rack to simulate internal conditions during takeoff.
“This is a one-off test in this family of super-heavy rocket boosters,” said John Honeycutt, SLS program manager at NASA’s Marshall Space Flight Center in Huntsville, Alabama. Seeing four RS-25 engines ignite at the same time in the core stage for the first time is an important milestone for the SLS.”
The four RS-25 engines fired for over a minute and produced 1.6 million pounds of thrust. Source: NASA TV.
According to NASA, this test is the eighth and final test in the “Green Run” series of tests conducted by the agency since 2019. The successful SLS is the first step to launch the Artemis Program (aimed at NASA). put 2 astronauts 1 male, 1 female to land on the Moon in 2024) of the US in the near future.
“Saturday’s test is an important step forward to ensure that the core stage of the SLS rocket is ready for the Artemis I mission and to carry crew on future missions.” , said NASA Director Jim Bridenstine, who attended the test. “Although the engine didn’t fire the entire time, the team successfully worked on the countdown, activating the engine and obtaining valuable data to pave the way for our journey ahead.”
With the success of the booster core, the SLS is officially the most powerful space rocket ever activated on Earth. The previous record-holder, the most powerful rocket booster system on the planet was also built by NASA – named Saturn V – the rocket that brought NASA’s Apollo 11 spacecraft to the Moon successfully in 1969.
The SLS (space rocket) booster is the largest, most powerful rocket ever built. Each booster produces more thrust than 14 four-engine commercial airliners. A pair of boosters provide more than 75% of the total SLS thrust at launch.
According to the plan, SLS will bring the Orion spacecraft to the Moon in 2024. Source: NASA
The rocket is manufactured by Northrop Grumman in Utah. At the launch point, the booster carries all of the SLS’s fuel. After launch, the boosters operated for 2 minutes before separating from the central stage.
The thrust of the SLS varies depending on the launch configuration. The lowest is 3991.6 tons for crew ships and the highest is 4309 tons for cargo. Equivalent to that is the load of the system, the lowest is 27 tons and the highest is 46 tons.
Main booster specifications (SLS has 2 boosters)
Kathy Lueders, newly appointed captain of NASA’s manned flight program, has released new cost estimates for the SLS super rocket. As of August 27, the cost is estimated at .1 billion. In addition, the cost of the ground support system was .4 billion. Earlier, the US Congress approved a plan of 7 billion dollars, according to the 2019 fiscal year.
In April, the estimated cost for SLS was .75 billion and the ground infrastructure system (EGS) was 2.33 billion. According to NASA, the previous cost calculated in 2014 for the two systems was 7.02 billion and 1.84 billion. Thus, the amount of the price has exceeded the 30% threshold that NASA was warned before, Space.com information.
Critics have long argued that NASA should transition from core shuttle-age technologies, which have launch costs of billion or more per mission, to commercial alternatives. Newer promises lower costs.
For comparison, the least expensive to launch the massive but less powerful Falcon Heavy from Elon Musk’s SpaceX is million; and about 0 million per launch of United Launch Alliance’s Delta IV Heavy. While the rockets are newer, more reusable.
Like many rockets, the rocket’s propulsion is delivered in stages:
During takeoff, the SLS core stage and two solid-fuel boosters worked to propel the 5.75-million-pound rocket off the launch pad at Kennedy Space Center in Florida and into orbit, carrying a spaceship named Orion.
To do this, in just eight minutes, the SLS’s four RS-25 engines burn 735,000 gallons of liquid fuel to produce 2 million pounds of thrust, and twin boosters burn more than two million pounds of solid fuel to generate out over 7 million pounds of thrust.
During the ascent, rocket engineers often say that the rocket is going uphill, a way to liken this stage of launch to carrying a huge weight up a mountain with the gravity of the Earth sucking everything up. down to the ground.
After the SLS lost the weight of its propulsion system and early-stage fuel, more power was still needed to bring the Orion spacecraft to the Moon. At this point, the upper portion of the rocket and Orion are 100 miles above Earth, at more than 17,500 miles per hour, and begin a circular orbit around the Earth. This is low Earth orbit, commonly known as LEO.
Essentially, the SLS can put more than 95 tons into this low orbit with the Block I configuration. However, a deep space mission (to the Moon) requires a rocket booster that has to go far beyond the LEO with enough power. strength and speed to overcome Earth’s gravity; as well as having to carry the spacecraft even further to reach the Moon. Therefore, it has to reduce its cargo load, giving weight to fuel and power to accelerate.
On the second mission to carry Orion and its astronauts, Artemis II, the SLS will carry the Orion spacecraft and its crew farther than NASA astronauts did in the 20th century.
Like the Artemis I flight stage, the second flight will use the Block I version of the SLS. On the third flight – Artemis III, SLS will carry Orion with 2 astronauts on a mission in 2024 to land on the Moon.
The Americans, along with their international and commercial partners, will use the Moon as a “space shuttle” to test technologies and prepare for missions to Mars.
The ultimate development of the SLS is a Block 2 rocket that can carry crew and cargo or just cargo needed for the exploration of Mars or for planetary missions beyond the Solar System.