When a rocket launches into space, it creates a powerful blast of sound that can be heard—and even felt—miles away.
SpaceX’s Falcon 9, a rocket used for both human and satellite missions, is no exception.
Since its first launch in 2010, Falcon 9 has taken off more than 400 times, with many of those launches happening at Vandenberg Space Force Base in California.
Even though Vandenberg is located 60 to 100 miles away from Ventura County, residents sometimes hear and feel the effects of Falcon 9’s sonic booms.
These low-frequency sounds are created when the rocket speeds through the atmosphere faster than the speed of sound.
Unlike the sharp crack of a sonic boom from a fighter jet, the noise from Falcon 9 is deeper and more like a rumbling that can shake windows and walls. Indoors, it can even feel like a mini-earthquake.
As the number of Falcon 9 launches increases, so do reports of sonic booms in the surrounding areas.
Brigham Young University physics professor Kent Gee noted that launches are becoming more frequent as satellite missions grow, leading to more sonic booms heard across the region. Motivated by noise concerns from Ventura County residents, researchers from BYU and California State University, Bakersfield conducted a study in the summer of 2024.
They collected 132 measurements of sonic booms across 200 square miles, trying to understand how these powerful waves of sound affect communities.
Makayle Kellison, a graduate student at BYU, and Professor Gee presented their findings at a major acoustics conference on May 19. According to Kellison, the strength and sound of these booms are not the same every time.
They can change depending on weather conditions, the time of day, the rocket’s path, and even the season.
This is different from sonic booms caused by aircraft, which are usually sharper and more sudden. Falcon 9’s booms are deeper, with most of their energy below 1 hertz—far lower than the range of human hearing. Instead of causing ear-piercing noise, these low frequencies make the ground and buildings shake.
In 2024 alone, Falcon 9 launched 46 times from Vandenberg, almost once a week. But not every launch produces a boom that reaches the ground, and when it does, the effect can vary. For some, it might just be a distant rumble, while for others, it might feel like a quick tremor.
The research team hopes their findings will help officials at Vandenberg Space Force Base understand the factors that influence sonic booms.
With this knowledge, they aim to improve planning and reduce noise impacts as rocket launches continue to increase.
Their work also opens the door for better policies to manage noise for communities living near rocket launch sites, supporting the growth of space exploration without major disruptions.
