BYU researchers capture the sound of the world’s most powerful rocket coming to life

What is the power of the most powerful rocket in the world when it roars?

A group of Brigham Young University researchers discovered on Nov. 16 that NASA’s Space Launch System rocket ignited, turning the night sky into day and propelling the unmanned Orion crew capsule into space during of a mission marking the first step towards the return of humans to the moon. and beyond.

BYU’s research team of undergraduate and graduate students, led by Professors Kent Gee and Grant Hart of the school’s Department of Physics and Astronomy, has come a long way to complete its recording. high-fidelity multipoint of the launch of the Artemis I mission from Kennedy Space Center. in Cape Canaveral, Florida.

A small grant got the project started, which took about 18 months of planning and preparation. Then a series of problems plagued NASA’s attempts to get the Artemis I mission off the ground, including pesky fuel leaks and a pair of hurricanes that swept through central Florida.

Why Assessing Rocket Launch Sound Matters

While the road to completing the recording was rocky, it’s work that the researchers say will help to figure out how to deal with the impacts of the massive sound emissions from an increasing number of rocket launches that take place at the United States and around the world.

A recent example of the kinds of impacts created by frequent rocket launches was highlighted in a US Fish and Wildlife report on SpaceX’s plans to build a commercial rocket launch site in Boca Chica, Texas.

The Fish and Wildlife Service analysis determined that if SpaceX goes ahead with the proposal, it would impact some species protected under the Endangered Species Act, as well as hundreds of other species. acres of their critical habitat, although the activity would not completely eliminate these species, according to a May report from CNBC.

Of most concern is the anticipated impact of the undertaking on the mating, migration, health and habitat of populations of piping plovers, red knots, jaguarundi and ocelots. According to CNBC, disturbance and damage can be caused by everything from regular vehicle traffic to noise, heat, explosions and habitat fragmentation caused by construction, rocket testing and launches.

And, a 2018 paper by researchers at the Georgia Institute of Technology noted that “despite the increase in rocket launches in recent years and the commercialization of their operations, little work has been published assessing the community noise impacts of operations. of rockets”. The authors suggest that further work on noise modeling studies would lead to a better understanding of potential noise exposure issues for communities near rocket launch facilities.

Here a launch, there a launch

This isn’t the first time the BYU team has made launch recordings, with previous field trips capturing audio from rockets including United Launch Alliance’s Delta IV Heavy, SpaceX’s Falcon 9 and Falcon Heavy and Alpha from Firefly Aerospace.

With an early research paper on SLS sound recordings currently being considered for publication, Gee has not been able to share all of the data on the latest sound recordings. But he noted that launching the world’s most powerful rocket – the SLS produces 8.8 million pounds of peak thrust, 15% more than the Saturn V rockets that launched Apollo astronauts to the Moon – eclipsed the team’s previous work, volume-wise.

“It’s hard to describe the experience, the energy is so huge,” Gee said. “Our recordings show that sound energy is greatest at frequencies so low that they are below our normal hearing range. So you’re as likely to feel the launch as much as you hear it.

“But even a few kilometers away, the maximum noise level was well over 120 decibels. It’s like being at an air show and having a military jet roaring overhead…but only a few hundred feet away.

BYU researchers captured the launch soundtrack from 14 recording stations in a network around Kennedy Space Center’s launch pad 39B and placed at varying distances from the site. Due to NASA security restrictions in the blast zone, most stations had to be set up and then left unmanned for the actual launch.

Gee said this is one of the most nerve-wracking aspects of capturing launch audio, as recording performance cannot be monitored and success, or failure, is only known. long after the rocket has left the ground.

A new definition of the strong

BYU student researcher Taggart Durrant, who has been involved in many other field recordings, said the in-person experience of the Artemis launch was unique.

“I was 10 miles away and it literally shook me,” Durrant said. “It was so bright it felt like the sun had just risen. That low-frequency rumble and high-pitched crackle…it’s almost otherworldly. Watching that huge rocket from the size of of a skyscraper taking off and making one of the loudest noises you’ve ever heard…it blew my mind.

And, Durrant noted, the sonic energy of rocket launches goes far beyond the experience.

“Launch acoustics are so loud that they can damage the launch pad structure and even spacecraft payloads,” he said. “They can have huge impacts on wildlife living on or near the base. And there’s the community side, with more and more rocket launches increasing community exposure.

“We hope to evaluate and improve rocket noise models. Anything to understand it better, so we can quantify or mitigate those impacts.

Gee noted that launch acoustics research has been largely ignored since the end of the Apollo program some 50 years ago, but the increasing number and frequency of rocket launches, in the United States and around the world, have increased in recent years.

The space economy takes off

In a report released in late November, McKinsey & Co. assessed a booming global space economy and associated rocket launch volumes, which are experiencing an accelerating arc of growth, particularly in recent years.

“These activities, once primarily the domain of government agencies, are now possible in the private sector as recent technological advances in manufacturing, propulsion and launch have made it much easier and cheaper to venture into space and to conduct missions,” the McKinsey researchers wrote. .

“The drop in costs has opened the door to new start-ups and encouraged established aerospace companies to explore new opportunities that once seemed too expensive or difficult. Technological improvements have also intrigued investors, leading to an increase in space funding over the past five years.

If you throw it they will come

The growing volume of rocket launch activity underscores the real benefits of BYU’s quest to build a deeper and more detailed understanding of the acoustic impacts of firing these massive engines. But it also provides growing career opportunities for students like Durrant and fellow BYU colleague and senior Michael Bassett.

Durrant is applying to graduate schools and considers her research experience a great addition to her resume, as well as an invaluable part of her educational experience and preparation for the world of work.

“Being part of the research team is definitely a great resume piece, but more than that, I’ve developed a skill set that I otherwise wouldn’t have had,” Durrant said. “That’s one of the reasons why I wanted to get into this field. We are beginning a new space age where there are more opportunities than ever. Space is not just what big governments do. It has become interesting and profitable for ordinary people.

Bassett called working on research projects with Gee and his other instructors and fellow students a “great opportunity to really understand the fundamentals and their real-world applications beyond classroom work.” And while he’s still debating his next steps after completing his work on an applied physics degree, he definitely sees continued research as part of his future.

“I feel like I really enjoyed working with Dr. Gee, and the side he has me working on, researching and developing the technologies to go along with this acoustic recording,” Bassett said. “Understanding how to overcome obstacles on projects like these, how to optimize equipment for the best results, that might be where I could go further in my research.”

Gee, who also chairs BYU’s Department of Physics and Astronomy, pointed out that research into rocket launch acoustics has been a student-led effort from the start and is producing amazing results while building confidence and skills of a new generation of scientists.

“It’s just a great experience for students,” Gee said. “They trained for it, prepared and executed the recordings perfectly. They were ready for now.