“Sonic showers” are a common technology referenced in the Star Trek universe. They are used in place of water-based showers and save resources on spacecraft, where every bit of mass and volume is a precious commodity.
Characters on the show often reference sonic showers, but the devices are rarely seen. In the Star Trek: Strange New Worlds episode “Under the Cloak of War, the franchise gave us a fresh look inside one.
We’ve seen inside sonic showers a few other times on Star Trek. Most recently, we saw a communal sonic shower on Star Trek: Lower Decks.
Star Trek: Voyager also featured a more detailed sonic shower scene, one that actually showed the dirt being vibrated off B’Elanna Torres.
The sonic shower also made an appearance in Star Trek: The Motion Picture when the V’Ger version of Ilea emerged from inside one.
So how does this strange device work? How can you take a shower without water? The exact specifics of how a sonic shower works are never fully explained in the Star Trek canon. However, the term “sonic” suggests it operates on principles of sound or vibration, much like how an ultrasonic cleaner works.
Ultrasonic cleaners are real-world devices that use high-frequency sound waves to create tiny, rapidly collapsing bubbles in a liquid medium (a phenomenon known as cavitation). These bubbles produce shock waves that dislodge dirt, grease, and other contaminants from surfaces immersed in the liquid, making them very effective cleaning devices.
Theoretically, a sonic shower might work similarly but without the liquid medium, using targeted sound waves to vibrate dirt and grime loose from the skin. This would be an extremely efficient way to clean, as it wouldn’t require water or cleaning products, just energy to produce the sound waves.