How space “sounds”
Sound is a physical phenomenon that is elastic waves propagating in a specific environment. In a narrow sense, sound is understood as vibrations perceived by the hearing organs of animals and humans. The eardrum in our ear picks up high-frequency changes in air pressure, and the brain processes the received signal.
In space, we do not hear anything, because there is no environment suitable for the propagation of sound. However, we will find out if a supernova explosion occurs near our planet, the “explosion” will be the result of the deformation of the Earth’s atmosphere under the influence of light.
However, if we are talking about electromagnetic vibrations that a person is not able to perceive, then their transformation into an audio format can give interesting and valuable results. For example, in this video, NASA processed the received signals from different planets:
Geektimes have already talked about NASA’s SoundCloud account, which opens the door to the world of “space” sounds (for example, a digitized recording of sounds from Voyager’s golden record was published), and cited a synthesized recording of sound from Venus as an example of what can be recorded on surface of the planet.
But back to the “sounding planets”. Radio waves emitted by celestial bodies can be read using a special device – an interferometer.
Interferometers are widely used in astronomy to create high-resolution radio and optical telescopes. An example is the giant ALMA radio telescope, which consists of more than 66 antennas spread over a large area that receive radio waves emitted by astronomical objects.
The principle of operation of the astronomical interferometer is as follows: suppose that two antennas are directed towards the cosmic body X. Since radio waves travel in outer space at a constant speed, radio waves from the object X will reach antennas spaced at a certain distance from each other at different times. After that, the signals of the two antennas can be interferred and the desired information about the source can be extracted from the resulting signal.
Optical telescopes, like our eyes, are imperfect and only allow observations in the visible range of radiation. ALMA, on the other hand, was specially developed for recording long waves. Thanks to this, scientists were able to look into the most distant corners of the Universe, hidden from our eyes by clouds of gas and cosmic dust.
The International Space Station is another project that aims to expand our knowledge of space. And here’s an interesting question, what does the ISS sound like? Experts who train astronauts to fly to the station say that everything sounds exactly the same there as it does on Earth.
The International Space Station itself consists of modules, and its interior resembles narrow cylindrical corridors. There are 14 modules in total, each of which contains research laboratories, utility rooms, warehouses, sleeping places, simulators. In this regard, the ISS is a rather noisy place: fans tirelessly drive air throughout the station. All this resembles several dozen computers “overloaded” with processes, whose coolers rotate at a breakneck speed and create a fairly strong hum.
In addition to fans, the ISS has a large number of pumps, compressors and other devices that emit sounds, for example, a special space simulator ARED, in which a cunning system of cylinders, levers and discs provides a load of up to 600 kg. Astronauts need to train, and lifting an ordinary barbell in space is inconvenient and useless.
The noise level on the ISS varies from 58 to 72 decibels (maximum 80). Of course, all parts of the station sound different: the noise level on the ISS can be estimated from the video below (note how the sound changes at 24 minutes when you go to the Russian space module).
If you don’t like video tours around the station, astronaut Chris Hadfield has uploaded several audio tracks recorded in various parts of the ISS to SoundCloud. Moreover, he even recorded the song, accompanying himself on the guitar.
Many musical compositions are able to very accurately convey the feeling of space and immerse us in a cosmic mood in a matter of seconds. Someone believes that the largest number of cosmic associations are associated with the songs of David Bowie. Listening to them, you are like going on a long journey.
Others advise paying attention to the classic works of Gustav Holst “Planets”:
There are even more interesting options:
Or the “Inception” app Wired talked about: