January 10, 2014
NASA’s CRaTER Radio Brings Listeners The Sounds Space
Brett Smith for redOrbit.com - Your Universe Online
A new NASA-backed Internet radio station from the moon may not have Miley Cyrus on its playlist or give away free concert tickets to the seventh caller, but scientists from the space agency are expecting it to be a hit with astrophysicists.
The CRaTER Live Internet Radio Station takes cosmic radiation data on a live stream from NASA's Lunar Reconnaissance Orbiter and converts it into a constant flow of soothing cosmic music. The station has been programmed to select various instruments and pitches based on radiation levels.
"Our minds love music, so this offers a pleasurable way to interface with the data," said project leader Marty Quinn of the University of New Hampshire. "It also provides accessibility for people with visual impairments."
The radiation data for the station is collected from LRO's Cosmic Ray Telescope for the Effects of Radiation (CRaTER). CRaTER monitors the charged particles from galactic cosmic rays and solar events using an array of six detectors.
CRaTER is focused on two primary objectives: determining the interaction of cosmic radiation with a material that is like human tissue, and observing the radiation’s interaction with the Moon, which scientists use to explore the make-up of dust on the lunar surface.
"CRaTER has discovered wide-ranging and fundamental aspects of such radiation," said Nathan Schwadron, the principal investigator for CRaTER. "For example, we have discovered that tissue-equivalent plastics and other lightweight materials can provide even more effective protection than standard shielding, such as aluminum."
Each CRaTER detector registers the number of particles it receives every second. Data from these detectors are sent to CRaTER Live Radio, where a computer program translates the numbers into pitches in a four-octave scale. Six pitches are played every second, one for each detector – with higher pitches signifying less activity and lower pitches indicating more activity.
The program behind the radio station also changes the stream’s primary instrument and a musical key based on data. At the lowest levels of activity, a piano is featured as the main instrument playing pitches from one of the major scales. As the radiation levels increase, the music will shift to a minor key and the piano will fade out for one of seven other instruments.
For example, a solar flare on January 7 changed the featured instrument to a marimba, which is two instruments up from the piano. Had radiation levels gone higher, the marimba would have been switched out for a steel drum, guitar or banjo – which are used for radiation levels at the top of the normal operating range.
If levels pass above the normal range, the station is kicked up to a second operating stage, with a piano again representing the bottom instrument and the banjo the top. To indicate which operating range the station is currently on – a violin and a cello play sustained notes in the background at a certain pitch on the scale. If those notes are played at the top of the scale, the normal range is in effect; if those notes drop in pitch, the second range is being used.
NASA has made the data-based radio station available through both a website an app.
"Music makes it easy for people to take in the data, and it seems to be a natural fit for space missions," said John Keller, LRO's project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.