AfterGlow Access, the Sonification Software

by Nikhil Vohra

Funded by the National Science Foundation, the IDATA Project (Innovators Developing Accessible Tools in Astronomy) aims to support the learning and participation of people who are blind, visually impaired, and sighted in the field of astronomy. The project’s recently updated flagship product, now called AfterGlow Access, is a sonification tool—a software that produces auditory, rather than visual, representations of data.  Its mission is to allow the blind and sighted alike to explore the images captured by space telescopes via sound. A member of the project’s team, Timothy Spuck from Associated Universities, Inc., recently joined Jeff Thompson on the Blind Abilities podcast to discuss the program and its potential to revolutionize science education and data analysis. Spuck begins by explaining that telescopes do not simply “see” pretty pictures of outer space when they are pointed into the night sky. Rather, they collect numerical data from the light they capture, and a computer takes this data and transforms it into pictures of outer space. At this part of the process, AfterGlow Access steps in. Instead of simply turning the data into an image by means of data visualization, the program turns the raw numbers collected by the telescope into sound via sonification. Spuck says, “[Y]ou often hear a picture is worth 1000 words, well, how many words is a song worth?” The software sweeps across the data that are transformed into image pixels row by row, emitting a stream of sound that encodes information about each pixel as it moves from left to right, from the bottom row of pixels to the top. Pitch, volume, and timing are employed to convey the state of a pixel (i.e., its position and brightness), and with training, a listener can make out a mental representation of the image. The process sounds complicated, but Spuck says that he and his team have had success in communicating data in this way. To listen to the podcast, which includes some examples of sounds made by the software, visit the Blind Abilities podcast site. To try the free, browser-based AfterGlow Access software for yourself, visit the IDATA Resources page. Note that either a Google account or Skynet account is required to try the software.