A Rocking Space Duet Featuring an Explosive Riff

R Aquarii, All Wavelengths

Credit: X-ray: NASA/CXC/SAO/R. Montez et al.; Optical: Data: NASA/ESA/STScI, Enhanced processing by Judy Schmidt (CC BY-NC-SA). X-ray/Optical composite processing by CXC/N. Wolk & K.Arcand; Sonification: NASA/CXC/SAO/K.Arcand, SYSTEM Sounds (M. Russo, A. Santaguida)

The system called R Aquarii unfolds dramatically through the eyes of NASA’s Chandra X-ray Observatory (purple) and Hubble Space Telescope (red and blue). The spectacular structures outlined in the Hubble data are old notes, or in other words, evidence from outbursts generated by a pair of stars buried at the center of the image. X-rays from Chandra reveal how a jet from one of these stars — a cool stellar ember known as a white dwarf — is banging into the material surrounding it. This high-powered flow creates shock waves, similar to sonic booms from planes that move faster than the speed of sound. The other player with the white dwarf in this interstellar duet is a red giant star. As they orbit each other, the white dwarf pulls material from the red giant onto its surface. Over time, enough of this material accumulates and triggers an explosion. Astronomers have seen such outbursts over recent decades and this dynamic chorus will likely go on for millennia to come.

Recently, a team of scientists has taken the data collected by Chandra and Hubble of R Aquarii and rendered it into sounds through the process known as “sonification”. Keeping true to the original data, sonification represents the astronomical data, through a translation, in forms that the human ears can decipher. In the sonification of R Aquarii, the piece uses a radar-like scan, starting at 12 o’clock and moving in a clockwise direction. The volume changes in relation to the brightness of sources in Hubble’s visible light image, while the distance from the center dictates the musical pitch (higher notes are farther out). The deep thuds toward the four corners are “diffraction spikes,” which are artifacts due to the bright central star. Likewise, the volume of sound representing the Chandra data changes with the brightness of the X-ray sources with the higher notes farther away from center. Listeners can hear jets from the white dwarf as the cursor travels near the two o’clock and eight o’clock positions. The ribbon-like arcs captured by Hubble create a rising and falling melody that sounds similar to a set of singing bowls. The Chandra data are rendered to sound more like a synthetic and windy purr.

— Megan Watzke & Kim Arcand

R Aquarii, X-ray (Chandra)

Credit: X-ray: NASA/CXC/SAO/R. Montez et al.; Sonification: NASA/CXC/SAO/K.Arcand, SYSTEM Sounds (M. Russo, A. Santaguida)

R Aquarii, Optical (Hubble)

Credit: Optical: Data: NASA/ESA/STScI, Enhanced processing by Judy Schmidt (CC BY-NC-SA); Sonification: NASA/CXC/SAO/K.Arcand, SYSTEM Sounds (M. Russo, A. Santaguida)