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Insulation applied to final SRB segment for Artemis 2 mission

Insulation is applied to the final SLS booster segment for the Artemis 2 mission. Photo Credit: NASA

Insulation is applied to the final SLS booster segment for the Artemis 2 mission. Photo Credit: NASA

NASA’s road back to the Moon has taken another step forward with technicians applying insulation to the final booster segment for the second flight of the Space Launch System.

SLS is the rocket NASA plans to use to return astronauts to the Moon under the Artemis program. It uses Shuttle-derived technology and is expected to be the most powerful rocket ever built, according to the U.S. space agency.

It’s main purpose is to send the Orion multipurpose crew vehicle with four astronauts and supplies to cislunar space for the first time since Apollo 17 in December of 1972.

The first flight, dubbed Artemis 1 (formerly Exploration Mission-1) is expected to send an unpiloted Orion around the Moon no earlier than late 2020. Artemis 2 is expected to send an Orion spacecraft with four astronauts on a free-return trajectory around the Moon as early as 2022.

The insulation for the twin solid rocket boosters to be used for Artemis 2 was applied by technicians at Northrop Grumman’s solid rocket motor production facility in Promontory, Utah. During launch, the insulation protects the booster segments’ casing from the enormous heat generated when the solid fuel is ignited.

At 177 feet (54 meters) tall and 12 feet (3.7 meters) wide, the twin five-segment boosters for the SLS are the largest and most powerful solid-fueled motors ever built. They each burn polybutadiene acrylonitrile to produce about 3.6 million pounds (16,000 kilonewtons) of thrust for 126 seconds, providing 75% of the rockets total thrust.

Each of the boosters five segments—one more than the Space Shuttle SRBs—use asbestos-free insulation. With 25% more propellant than the Shuttle-era motors, a new nozzle design and new avionics, the SLS boosters are considered an improvement.

However, unlike their precursors, they are not planned to be reused and are expected fall back to Earth after being jettisoned from the SLS core to crash into the ocean and become artificial reefs at the bottom of the Atlantic.

According to NASA, all 10 of the motor segments for Artemis 1 were checked out earlier in 2019. Under the Artemis program, the U.S. space agency plans to utilize commercial partnerships to construct the Lunar Gateway to serve as a staging point to assemble a commercial lunar lander before sending astronauts to transfer to the lander to descend to the Moon’s surface.

The first human lunar landing of the 21st century is planned to be aboard Artemis 3 in 2024.

SLS Block-1 on launchpad at night

A rendering of an SLS Block 1 rocket on the launch pad at night. Image Credit: NASA



Collin R. Skocik has been captivated by space flight since the maiden flight of space shuttle Columbia in April of 1981. He frequently attends events hosted by the Astronaut Scholarship Foundation, and has met many astronauts in his experiences at Kennedy Space Center. He is a prolific author of science fiction as well as science and space-related articles. In addition to the Voyage Into the Unknown series, he has also written the short story collection The Future Lives!, the science fiction novel Dreams of the Stars, and the disaster novel The Sunburst Fire. His first print sale was Asteroid Eternia in Encounters magazine. When he is not writing, he provides closed-captioning for the hearing impaired. He lives in Atlantic Beach, Florida.

Reader Comments

Is insulation applied to the inside of the booster section or the outside?

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