Have You Ever Wondered What Space Sounds Like? Well, It Sounds Absolutely Terrifying

The complex interplay between the planet Jupiter and its volcanic moon, Io, produces "radio noise storms", which can be heard on the radio band from about 15 MHz up to 38 MHz. A storm can last from a few minutes to several hours. Two distinctive types of bursts can be received by radio astronomers during a storm. L-Bursts (long bursts of radiation) vary slowly in intensity with time, lasting from a few seconds to several tens of seconds and have bandwidths of a few MHz. L-Bursts sound like ocean waves breaking up on a beach. S-Bursts (short bursts of radiation) have durations of a few thousandths to a few hundredths of a second and can occur at rates of tens of bursts per second. Groups of S-Bursts sound like popcorn popping, or like a handful of pebbles thrown onto a tin roof.

The Sun is also a very commonly heard object via radio astronomy. When there is a solar flare on the Sun's surface, it is often accompanied by a burst of radio energy projected into space. This energy can be monitored with standard ShortWave and VHF radio receivers. Solar bursts typically last from half a minute to a couple of minutes and often sound like a rapid hissing noise followed by a gradual decrease back to the original audio level.

Audio can also be used to describe more distant and abstract phenomena in space. Pulsars are a good example. A pulsar is a small spinning neutron star which contains an enormous amount of energy which causes it to turn on its axis, or rotate, very rapidly. Pulsars rotate between less than 1 time per second up to 642 times per second. It is very difficult for us to understand the significance of this through visual media. But audio or data sonification can really bring this to life. For example the B0329+54 Pulsar rotates around 1.40 times per second. Each rotation can be heard as a click, or a beat, and through audio it sounds like a slow steady metronome. The Vela Pulsar, lies near the centre of the Vela supernova remnant, which is the debris of the explosion of a massive star about 10,000 years ago, rotates at about 11 times per second, and thus has a much faster rhythm

The terrific amount of energy it takes to spin a star on its axis at this pace, and the speed at which these rotations take place, is more easily signified in audio, than in visual media.

Radio Astronomy is an attempt to depict some of these complex audio events.

Broadcasting The Music Of The Spheres

The history of 20th century avant-garde music and sound art has been marked by the radical expansion of the notion of musique concréte. Emanating originally from Pierre Schaeffer's experiments with natural sounds recorded and played back in a musical context, musique concréte has become a framework of thinking about musical forms created from non-musical, or 'found', sounds. Parallel challenges to the definition of music have been issued by many 20th century composers - Alvin Lucier, John Cage, Karlheinz Stockhausen, Iannis Xenakis, to name but a few. John Cage's iconic 4.33 challenged audiences to listen to their ambient surrounds, taking into account the aesthetic and conceptual qualities of the performance location. Stockhausen conceives of technological tools such as microphones, transmitters and recording devices as being musical instruments. These pioneering theoretical positions have created a context whereby musicians are able to count among their compositional tools and performative instruments most naturally occurring or man-made sounds. What at first may appear to be non-musical sound, can be heard and contextualised as musical by the subtle intervention of a musician or sound artist.

Radio Astronomy can be interpreted as existing within this avant-garde tradition. A musique concréte reading of the project would depict the telescopes as grand concréte instruments, performing an ongoing and automated composition, nuanced by the complex interplay of the astronomers' target observations, the atmospheric conditions of a particular period, and the operational condition of the telescopes.

Avant-garde contemporary electronic music can also give us conceptual apparatus to examine the aesthetic output of the radio telescopes utilised in Radio Astronomy. Music created by experimental electronic musicians using laptop computers and software such as Reactor, MaxMSP and PureData(PD) is often characterised by its use of crackles, pops, hisses, ticks and other digital detritus caused by the digital processing of audio. This music, often referred to as 'glitch music' and exemplified by musicians such as Oval, Kim Cascone, Ryoji Ikeda, Matmos, Fennesz and many others, has become an important part of electronic culture. The aestheticisation of the 'mistake' or 'glitch' which so exemplifies this type of music has helped usher in a new appreciation of 'noise' and 'sonic artefacts' within music composition.