Can You Hear the Engine in Space?

As a space engineer at Google, it's fascinating to explore the unique properties of sound in the absence of air. A question often arises regarding the sounds produced in space by the engines of spacecrafts. Let's delve into the scientific principles to understand if it is possible to hear the engine in outer space.

Sound Requires a Medium to Travel Through

Sound is a wave that needs a medium (like air or water) to propagate. In the vacuum of space, there is virtually no air or other particles to allow the transmission of sound waves. Consequently, it is not possible to hear the engine of a spacecraft in the true sense when you are in space outside the ship.

How Sound Travels Inside a Pressurized Spacecraft

However, inside a pressurized spacecraft, the situation changes. The engine generates vibrations when it operates, and these vibrations can be transmitted through the solid structure of the spacecraft. The air inside the cabin plays a crucial role in carrying these vibrations to the astronaut's ears. Here's a step-by-step explanation:

The engine's vibrations are initially transmitted through the spacecraft's structure. The vibrations are then carried through the air inside the cabin. The air molecules transfer the vibrations to the astronaut's eardrums, allowing the brain to interpret them as sound.

Therefore, if an astronaut is within a pressurized cabin, they can potentially hear the engine through the structure of the spacecraft, even if they are far from the source of the engine.

Vibrations and Engine Operation

Understanding the relationship between vibrations and engine operation is important. Since the engine is physically connected to the spacecraft, vibrations are inevitably transmitted to the surrounding structure. This is how the engine can be detected even in the absence of sound.

However, the ability to hear the engine is not guaranteed and depends on various factors. These include the distance from the engine, the materials the engine and spacecraft are made from, and the noise level output by the engine.

Conclusion

In conclusion, while the engine of a spacecraft cannot be heard in the vacuum of space, it can be detected through vibrations inside a pressurized cabin. The key factor is the presence of a medium (like air) within the cabin to carry the vibrations to the astronaut's ears. This understanding is crucial for designing and managing the comfort and safety of astronauts during their missions in space.