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ALMA Sound: True Music of the Spheres

There has always been a connection between astronomy and music. In fact, if you go all the way back to the ancient Greeks, Pythagoras first identified the relationship between musical pitch and numerical ratios. He discovered the ratio, 2:1, of the octave. That means a string and a string with exactly half the length will sound in perfect consonance. In fact the Greek word for ratio is logos. A perfect fifth has the ratio (logic) of 3:2. A perfect fourth sounds in the ratio of 4:3. So if you look at many popular songs, they are still based on the the same logic or ratios.

In a philosophic theory known as the Harmony of the Spheres, Pythagoras suggested that celestial bodies emit their own unique vibrations based on their orbits,

“As the eyes, said I, seem formed for studying astronomy, so do the ears seem formed for harmonious motions: and these seem to be twin sciences to one another.

by Plato- Republic VII.XII

ALMA Sounds combines radio astronomy captured by the Atacama Large Millimeter/submillimeter Array (ALMA) and music. Astronomers Antonio Hales and Universidad de Chile engineer, Ricardo Finger determined a way to interpret the electromagnetic spectra of the Orion Nebula and transform them into digital sounds.

“The ALMA sound bank is made up of a series of drum shots created from the sound pattern of electromagnetic spectra from the Orion Nebula. The emission lines of molecules present in the Orion Nebula were transformed into musical notes, transposing the ‘chords’ from the skies into sound chords. The sound bank is, as its name implies, a digital library of sounds available to the musical community.”

by Astronomer Antonio Hales

At the  Sónar+D festival in Barcelona, Spain between 6 and 18 June 2016, the ALMA sounds project will have a stand with digital instruments with MIDI interfaces enabling the audience to interact directly with the ALMA Sounds cosmic sound bank . The Chilean collective Trimex will also present an artistic representation of the planets in the Solar System.

Here is a selection of songs that were done using the ALMA Sounds sound bank.  

The sound bank is is available for free download here.