A Universe of Sound

V404 Cygni Sonification

Video Description:
One of the surprising features of black holes is that although light (such as radio, visible, and X-rays) cannot escape from them, surrounding material can produce intense bursts of electromagnetic radiation. As they travel outward, these blasts of light can bounce off clouds of gas and dust in space, similar to how light beams from a car’s headlight will scatter off fog.

A new sonification turns these “light echoes” from the black hole called V404 Cygni into sound. Located about 7,800 light-years from Earth, V404 Cygni is a system that contains a black hole, with a mass between five and 10 times the Sun’s, that is pulling material from a companion star in orbit around it. The material is funneled into a disk that encircles the stellar-mass black hole.

This material periodically generates bursts of radiation, including X-rays. As the X-rays travel outward they encounter clouds of gas and dust in between V404 Cygni and Earth and are scattered at various angles. NASA’s Chandra X-ray Observatory and Neil Gehrels Swift Observatory have imaged the X-ray light echoes around V404 Cygni. Because astronomers know exactly how fast light travels and have determined an accurate distance to this system, they can calculate when these eruptions occurred. This data, plus other information, helps astronomers learn more about the dust clouds, including their composition and distances.

The sonification video of V404 Cygni features a hazy, bright blue dot surrounded by three concentric, glowing, deep red rings set against a black background. The rings of radiation are grainy and blurred, resembling curved tire marks left in wet snow. The smallest ring, closest to the blue dot at the core, is tightest and brightest. The largest ring, furthest from the core, is most faint and appears to have dissipated. The rings of radiation were observed as X-ray data collected by the Neil Gehrels Swift Observatory. In the sonification video, a thin white circle expands from the core. As it passes over the rings, the datapoints crackle. The brighter the ring, the louder the sound.

This sonification video of V404 Cygni features similar glowing concentric rings set against a black background. This time the radiation rings have been rendered in bright neon blue, representing data collected by the Chandra X-ray Observatory. Here, there are clean breaks in the visualized radiation at our upper corners and in a straight horizontal line across the center of the frame, as if portions of the rings were removed with swipes of an eraser. These blank spots represent areas outside of Chandra's field of view. As the thin white circle expands in this sonification video, the radiation it washes over is translated into higher-frequency popping sounds.

This sonification video of V404 Cygni features a black sky dotted with specks of white and pale blue light. These are the V404 Cygni system background stars, photographed by the Digitized Sky Survey. As the thin white circle expands in this sonification video, each star it encounters triggers a musical note. The volume and pitch relate to the brightness of the stars.

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The Chandra sonifications were led by the Chandra X-ray Center (CXC), with input from NASA's Universe of Learning. The sustained collaboration was driven by visualization scientist Dr. Kimberly Arcand (CXC), astrophysicist Dr. Matt Russo and musician Andrew Santaguida (both of the SYSTEM Sounds project). For other sonifications, please see their linked pages.

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Additional support from NASA's Universe of Learning (UoL). UoL materials are based upon work supported by NASA under award number NNX16AC65A to the Space
Telescope Science Institute, working in partnership with Caltech/IPAC, Jet Propulsion Laboratory, Smithsonian Astrophysical Observatory, and Sonoma State University.