New NASA Black Hole Sonifications with a Remix
https://youtu.be/ioR5np1fmEc
Since 2003, the black hole at the center of the Perseus galaxy
cluster has been associated with sound. This is because
astronomers discovered that pressure waves sent out by the
black hole caused ripples in the clusters hot gas that could
be translated into a note one that humans cannot hear some
57 octaves below middle C. Now a new sonification brings
more notes to this black hole sound machine. This new
sonification that is, the translation of astronomical data
into sound is being released for NASAs Black Hole Week
this year.
In some ways, this sonification is unlike any other done before
(1, 2, 3, 4) because it revisits the actual sound waves discovered
in data from NASA's Chandra X-ray Observatory. The popular
misconception that there is no sound in space originates with
the fact that most of space is essentially a vacuum, providing no
medium for sound waves to propagate through. A galaxy cluster,
on the other hand, has copious amounts of gas that envelop the
hundreds or even thousands of galaxies within it, providing
a medium for the sound waves to travel.
In this new sonification of Perseus, the sound waves astronomers
previously identified were extracted and made audible for the first
time. The sound waves were extracted in radial directions, that is,
outwards from the center. The signals were then resynthesized into
the range of human hearing by scaling them upward by 57 and 58
octaves above their true pitch. Another way to put this is that they
are being heard 144 quadrillion and 288 quadrillion times higher
than their original frequency.
(A quadrillion is 1,000,000,000,000,000.) The radar-like scan
around the image allows you to hear waves emitted in different
directions. In the visual image of these data, blue and purple both
show X-ray data captured by Chandra.
https://youtu.be/sKSVIbUNa3k
In addition to the Perseus galaxy cluster, a new sonification of
another famous black hole is being released. Studied by scientists
for decades, the black hole in Messier 87, or M87, gained celebrity
status in science after the first release from the Event Horizon
Telescope (EHT) project in 2019. This new sonification does not
feature the EHT data, but rather looks at data from other telescopes
that observed M87 on much wider scales at roughly the same time.
The image in visual form contains three panels that are, from top
to bottom, X-rays from Chandra, optical light from NASAs Hubble
Space Telescope, and radio waves from the Atacama Large Millimeter
Array in Chile. The brightest region on the left of the image is
where the black hole is found, and the structure to the upper right
is a jet produced by the black hole. The jet is produced by material
falling onto the black hole. The sonification scans across the
three-tiered image from left to right, with each wavelength mapped
to a different range of audible tones. Radio waves are mapped to
the lowest tones, optical data to medium tones, and X-rays detected
by Chandra to the highest tones. The brightest part of the image
corresponds to the loudest portion of the sonification, which is
where astronomers find the 6.5-billion solar mass black hole that
EHT imaged.
More sonifications of astronomical data, as well as additional
information on the process, can be found at the
A Universe of Sound website:
https://chandra.si.edu/sound/
