When we think of a space mission like Artemis II, we tend to focus on the technology, the rockets, or the exploration itself. But there’s a less visible aspect that also plays a key role: the crew’s hearing health.
As a hearing care specialist, I find it especially interesting to see how the human ear responds in extreme environments. Because although space may seem far removed from everyday life, many of the issues astronauts can experience are directly related to situations we see every day in the clinic.
In this article I want to explain what a space mission has to do with hearing, what risks are involved, and what we can learn to better look after our ears here on Earth.
What is the Artemis II mission
Artemis II is the first crewed mission of NASA’s Artemis programme, aiming to return humans to lunar orbit.
Unlike previous missions, it won’t land on the Moon, but it will allow all flight systems to be tested in real conditions with astronauts on board.
During this journey, the crew was exposed to:
- Intense vibration during ascent and re-entry.
- Extreme noise, both mechanical and ambient.
- Radical atmospheric pressure changes.
- Microgravity, which alters the distribution of bodily fluids.
And all of this directly affects the hearing system.
The physiology of the ear in microgravity
On Earth, the inner ear uses gravity to tell us which way is “up” and which is “down”. Inside the vestibule, the otoliths (tiny calcium carbonate crystals) press against hair cells depending on the tilt of our head.
In space, the otoliths float freely. The brain stops receiving the gravitational signal, but the eyes still see the walls of the capsule. This conflict between what the eye sees and what the inner ear senses causes Space Adaptation Syndrome. As hearing care specialists, we know that balance and hearing are closely linked, and a disturbance in one usually affects perception in the other.
Due to the lack of gravity, body fluids (blood and lymph) shift towards the upper torso and head. This causes swelling in the facial tissues and in the lining of the Eustachian tube. The result is a persistent feeling of blocked ears, similar to what our patients experience with allergic rhinitis or chronic congestion. While these effects are usually temporary, they show just how sensitive the hearing system is to small changes.
Extreme noise: the invisible enemy inside the Orion capsule
One of the myths about space is that it’s “silent”. While the vacuum outside doesn’t carry sound, the inside of a spacecraft is an extremely noisy environment.
The phases of noise during Artemis II
- Launch: The noise from the SLS engines generates low-frequency vibrations that can reach 150 decibels outside. Although the capsule is insulated, vibration is transmitted through the structure (bone conduction), reaching the astronaut’s inner ear directly.
- Life in orbit: Life-support systems, cooling fans and water recycling pumps run 24/7. Constant ambient noise on the station can hover around 70-80 dB. To put that in perspective, it’s like living inside a busy restaurant without ever being able to leave.
Prolonged exposure to this noise causes listening fatigue. The hair cells in the cochlea become exhausted, raising the hearing threshold and causing the astronaut to need communications repeated — a symptom we see every day in people with early hearing loss.
Noise-cancelling technology: from space to your hearing aids
This is where aerospace engineering and modern audiology shake hands. NASA can’t simply give astronauts earplugs, because they need to hear communications. This is where Active Noise Cancellation (ANC) comes in.
How does cancellation technology work?
Whether in an astronaut’s headset or in the high-end hearing aids we fit at our centre, the principle is the same: destructive interference.
- External microphones pick up ambient noise (engine hum or traffic noise).
- A digital processor generates a sound wave that’s the exact inverse (opposite phase).
- Both waves cancel each other out, creating “artificial silence”.
The risk of tinnitus in space
Many astronauts have reported developing tinnitus (ringing or buzzing in the ears) after their missions. The stress of launch, combined with fluid pressure and constant noise, can damage nerve endings.
On Earth, tinnitus is often a sign that the hearing system is under strain. During the Artemis II mission, astronauts keep a strict record of their tinnitus levels, since an increase in ringing can indicate that their hearing protection isn’t properly fitted. This teaches us a fundamental lesson: ringing is your ear’s alarm bell. Ignoring it is like ignoring a red warning light on a spacecraft’s control panel.
Can an astronaut go deaf?
It’s not common, but hearing risks do exist if the right precautions aren’t taken.
According to ENT specialists, the main problems that can arise are:
- Temporary hearing loss
- Ringing (tinnitus)
- A feeling of blocked ears
- Balance disturbances
In most cases, these effects are reversible, but that depends on the level of exposure and how well risk factors are managed.
What can we learn from astronauts?
You don’t need to be a NASA pilot to look after your ears like one. Here are the lessons from Artemis II applied to your everyday life:
- The acoustic rest rule: Astronauts have mandatory periods of silence to allow their hair cells to recover. You should do the same: if you spend the day in a noisy environment, give your ears a full hour of silence when you get home.
- Tailored protection: NASA doesn’t use standard earplugs — it uses moulds tailored to each astronaut’s anatomy. At our hearing centre in Valencia, we make custom protection that protects without isolating you, letting you hear voices while blocking harmful noise.
- Constant monitoring: Before, during and after the mission, high-resolution hearing tests are carried out. We recommend an annual check-up from age 50 onwards. Early detection is the difference between a simple solution and irreversible loss.
Communication: hearing vs. understanding
During the Artemis II mission, simply “hearing” isn’t enough. The astronaut has to understand complex data in high-stress situations. Conductive hearing loss (from pressure) or sensorineural hearing loss (from noise) reduces the brain’s ability to distinguish words.
This is the same challenge our patients face. When someone tells me “I can hear, but I can’t understand”, they’re experiencing the same thing as an astronaut with listening fatigue. The brain has to spend so much energy decoding sound that it becomes exhausted, causing tiredness, irritability and isolation. Modern hearing aids, just like the Orion capsule’s systems, ease that cognitive load, letting the brain focus on the message instead of the noise.
The Artemis II mission is a reminder that we’re biological beings exploring technological environments. Our ears are a piece of perfect organic engineering, but extremely sensitive to change. Whether you’re facing a rocket launch or the daily traffic on Calle Colón in Valencia, your ears deserve the same level of care and protection as a NASA astronaut’s.
Looking after your hearing is a daily decision that affects your balance, your memory and your connection with those around you. You don’t need to travel to the Moon to appreciate silence or the clarity of a loved one’s voice.
If you’re finding it hard to follow conversations, feeling persistent pressure or discomfort, if everyday noise leaves you exhausted, or if you’d simply like to get your hearing checked, our hearing centre in Valencia can help you understand what’s going on and find the best hearing solution for you, tailored to your needs.
Come and visit us, and make sure your ears are ready for whatever mission life throws at you.
Book your appointment today. Your journey towards better hearing starts here. You can call us on 960 659 592 or message us on WhatsApp at 621 00 16 93.
