Artemis II launch reveals unique seismic activity captured by USF scientists

By Joey Garcia, University Communications and Marketing

As millions watched Artemis II lift off from Kennedy Space Center, USF scientists remained on the ground, capturing rare seismic and infrasound data-insights that inform launch impacts on Earth.

USF researchers are no strangers to working with rocket launches. Over the past decade, the USF Seismology group, has recorded data from roughly 140 launches at Kennedy Space Center-a project led by Research Assistant Professor Glenn Thompson from the from the School of Geosciences in collaboration with NASA. Most of those launches were Falcon 9 rockets, which are known to be less intense.

Artemis II, however, marked a shift in scale.

LISTENING TO ROCKETS THROUGH THE GROUND AND AIR

Thompson and his team studied the Artemis II launch with the same seismic sensors used to record ground motion generated by earthquakes and volcanic activity. They also used infrasound sensors, which detect very low-frequency sound waves in the air that humans cannot hear but feel as vibrations.

Understanding how these rockets affect ground motion and sound pressure levels benefits a wide range of groups. Structural engineers use this information to assess infrastructure resilience. Wildlife biologists and ecologists study potential environmental impacts, while archaeologists consider possible effects on cultural and historical sites.

"For Artemis II, we deployed a record 12 seismic and infrasound stations surrounding the launch site within a 10-mile radius," Thompson said. "This allows us to study what happens when powerful sound waves in the atmosphere interact with the ground at this scale."

When the rocket ignites while connected to the launch tower, it generates direct seismic energy that travels quickly through the ground at several miles per second. However, a much larger effect comes from the rocket's intense jet noise, which produces powerful sound and infrasound waves. As those waves strike the ground, they generate vibrations that dominate the direct seismic signals recorded near the launch pad.

"We're essentially listening to the rocket through the atmosphere and the ground at the same time," Thompson said. "As rockets become more powerful and launches more frequent, having precise measurements allows these groups to evaluate impacts responsibly and ensure that launch activity remains safe and sustainable."

A UNIQUE SEISMIC DATASET

To better understand what's happening underground, researchers used the Artemis II launch as a powerful, large-scale energy source.

"By recording low-frequency sound waves and ground motion at the same locations, we can separate the sound from the seismic data," Thompson said. "That lets us focus on how the ground itself responds to pressure, helping us better understand what's happening below the surface."

To further strengthen the dataset, Thompson deployed state-of-the-art nodal seismic and infrasound sensors borrowed from the EarthScope Consortium and Boise State University.

Those instruments recorded peak pressure levels of about 600 pascals, equivalent to roughly 146 decibels. The Artemis II launch is among the strongest signals the team has ever measured. For comparison, those levels slightly exceed what researchers observed during a Falcon Heavy launch and are roughly four to five times higher than a typical Falcon 9 launch, reflecting the far greater power of NASA's Space Launch System.

Researchers will use this data to improve geological models beneath Cape Canaveral and Merritt Island and better understand how increasingly powerful launches may affect surrounding environments.

USF FIELDWORK LEADS TO LUNAR SCIENCE LEADERSHIP

Thompson's work at Kennedy Space Center has also focused on training students through hands-on field deployments.

"Over the years, I've taken dozens of students into the field, giving them hands-on experience deploying and maintaining seismic networks and using the data in classroom settings," Thompson said. "Many have gone on to careers in seismic monitoring and volcano observatories."

One participant in the first 2016 deployment was USF alum Jacob Richardson, now the deputy lunar science lead on the Artemis II lunar science team. His group has spent more than a year preparing observation strategies, including potential views of unexplored regions on the moon's far side.

"Jacob volunteered for that first deployment and was already an exceptional researcher," Thompson said. "It's wonderful to see a former USF Geosciences student playing such a big role in the Artemis program."

STRONGER SEISMIC RESEARCH

The Artemis II deployment is just the beginning of Thompson's next phase of seismic research. He is part of a NASA proposal to scale up the effort, deploying at least 75 seismic and infrasound stations ahead of a future SpaceX Starship launch from Kennedy Space Center, a vehicle expected to surpass the Artemis II launch system's power.

The project is led by Paul Bremner at NASA's Marshall Space Flight Center, with key collaborators including Aiden Woo (NASA marshall) and Sue Bilek (New Mexico Tech).

"The Artemis II deployment served as an important test run, allowing us to gain experience deploying the equipment, recovering it and processing the data," Thompson said. "The lessons learned and workflows developed will directly support the larger project."