1.09.2024
- Three new sonifications have been released to commemorate the 25th anniversary of Chandra’s “First Light” images.
- Cassiopeia A was one of the first objects Chandra observed after it launched into space on July 23, 1999.
- Sonification is a scientific and math-based process that translates data into notes and sounds.
- In addition to Cas A, the new sonifications include the star-forming region of 30 Doradus and the galaxy NGC 6872.
A quarter of a century ago, NASA released the “first light” images from the agency’s Chandra X-ray Observatory. This introduction to the world of Chandra’s high-resolution X-ray imaging capabilities included an unprecedented view of Cassiopeia A, the remains of an exploded star located about 11,000 light-years from Earth. Over the years, Chandra’s views of Cassiopeia A have become some of the telescope’s best-known images.
To mark the anniversary of this milestone, new sonifications of three images — including Cassiopeia A (Cas A) — are being released. Sonification is a process that translates astronomical data into sound, similar to how digital data are more routinely turned into images. This translation process preserves the science of the data from its original digital state but provides an alternative pathway to experiencing the data.
Cassiopeia A (above)
This sonification of Cas A features data from Chandra as well as NASA’s James Webb, Hubble, and retired Spitzer space telescopes. The scan starts at the neutron star at the center of the remnant, marked by a triangle sound, and moves outward. Astronomers first saw this neutron star when Chandra’s inaugural observations were released 25 years ago this week. Chandra’s X-rays also reveal debris from the exploded star that is expanding outward into space. The brighter parts of the image are conveyed through louder volume and higher pitched sounds. X-ray data from Chandra are mapped to modified piano sounds, while infrared data from Webb and Spitzer, which detect warmed dust embedded in the hot gas, have been assigned to various string and brass instruments. Stars that Hubble detects are played with crotales, or small cymbals.
30 Doradus (Tarantula Nebula):
Another new sonification features the spectacular cosmic vista of 30 Doradus, one of the largest and brightest regions of star formation close to the Milky Way. This sonification again combines X-rays from Chandra with infrared data from Webb. As the scan moves from left to right across the image, the volume heard again corresponds to the brightness seen. Light toward the top of the image is mapped to higher pitched notes. X-rays from Chandra, which reveal gas that has been superheated by shock waves generated by the winds from massive stars, are heard as airy synthesizer sounds. Meanwhile, Webb’s infrared data show cooler gas that provides the raw ingredients for future stars. These data are mapped to a range of sounds including soft, low musical pitches (red regions), a wind-like sound (white regions), piano-like synthesizer notes indicating very bright stars, and a rain-stick sound for stars in a central cluster.
NGC 6872:
The final member of this new sonification triumvirate is NGC 6872, a large spiral galaxy that has two elongated arms stretching to the upper right and lower left, which is seen in an optical light view from Hubble. Just to the upper left of NGC 6872 appears another smaller spiral galaxy. These two galaxies, each of which likely has a supermassive black hole at the center, are being drawn toward one another. As the scan sweeps clockwise from 12 o’clock, the brightness controls the volume and light farther from the center of the image is mapped to higher-pitched notes. Chandra’s X-rays, represented in sound by a wind-like sound, show multimillion-degree gas that permeates the galaxies. Compact X-ray sources from background galaxies create bird-like chirps. In the Hubble data, the core of NGC 6872 is heard as a dark low drone, and the blue spiral arms (indicating active star formation) are audible as brighter, more highly pitched tones. The background galaxies are played as a soft pluck sound while the bright foreground star is accompanied by a crash cymbal.
These sonifications were led by the Chandra X-ray Center (CXC) and included as part of NASA's Universe of Learning (UoL) program. The collaboration was driven by visualization scientist Kimberly Arcand (CXC), astrophysicist Matt Russo, and musician Andrew Santaguida, (both of the SYSTEM Sounds project), along with consultant Christine Malec. More information about the NASA sonification project can be found at https://chandra.si.edu/sound/.
NASA's Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
NASA's Universe of Learning materials are based upon work supported by NASA under cooperative agreement award number NNX16AC65A to the Space Telescope Science Institute, working in partnership with Caltech/IPAC, Center for Astrophysics | Harvard & Smithsonian, and the Jet Propulsion Laboratory.
Different telescopes detect different types of light. Much of what they capture is recorded as digital data. Those data can then be translated into visuals, or even sounds. In today’s release, the data from three different astronomical observations are presented in collections of visualizations, and sonifications. Just as each composite visualization includes data from different sources, each composite sonification represents multiple data sets from different telescopes. The collections presented here include sonifications of data from different light spectra, and composites with all related sonifications layered into a single video.
The first collection features observations of Cassiopeia A, the remains of an exploded star located about 11,000 light-years from Earth. The composite visualization of the remaining debris field resembles a churning ball of dark blue and red clouds, marbled and veined with purples, greens, reds, electric blues, yellows, whites, and oranges. In each of the related sonification videos, a small circle at the center of each image expands outward. As the growing circle sweeps past different elements, a variety of sounds are triggered. The brighter the light from each element, the louder and higher pitched the sound. In the James Webb Space Telescope visualization of Cassiopeia A, the debris field features marbled clouds of red, yellow, orange, green, and white. In the JWST sonification, musical instruments have been assigned to each color. Low pitched strings represent red, and high strings represent white. Low brass instruments represent yellow and orange, high brass represents blue, and woodwinds represent green. In the Chandra X-ray visualization, the brightness of the electric blue X-ray cloud is mapped to notes on a modified piano. And in the Hubble optical visualization, small cymbals called crotales chime when the expanding circle sweeps over a distant star. All of these instruments are combined in a symphonic sonification of the composite visuals.
The second collection features observations of 30 Doradus, one of the largest and brightest regions of star formation close to the Milky Way. In the composite visualization, a field of stars is partially obscured by a red nebula of cosmic gas and dust, and bright blue X-ray clouds. Near the center of the visualization, a break in the nebula, ringed with wispy white clouds, reveals a brilliant gleaming star, and the central star cluster of 30 Doradus. In the related sonification videos, a vertical line sweeps across the images from left to right, triggering musical sounds as different elements are encountered. The higher in the frame the element is, the higher the pitch of the sound. In the Chandra sonification, the mottled cloud of bright blue X-ray light is mapped to notes on an airy synthesizer. In the James Webb Space Telescope infrared sonification, the red nebula is mapped to soft low musical pitches, and the wispy white cloud is mapped to harsh, high frequency, wind-like sounds. Stars are played on a piano-like synthesizer, with percussion triangles indicating diffraction spikes. A rain-stick represents stars belonging to the central cluster. All of these instruments are combined in the composite sonification.
The third collection features observations of NGC 6872, a large spiral galaxy with elongated arms stretching toward our upper right and lower left. NGC 6872 is backed by a field of stars and distant galaxies, with a neighboring spiral galaxy beside it, to our left. The two galaxies, as well as several bright stars, are engulfed in a neon purple cloud of X-ray gas. In the related sonification videos, a radial arm sweeps clockwise around the images, starting at twelve o’clock, triggering musical sounds as different elements are encountered. The volume of the music is mapped to brightness, and the pitch is related to the distance from the center; the farther away, the higher the pitch. In the Hubble sonification, a low drone represents the core of NGC 6872, while higher, brighter sounds represent the extended spiral arms. Low plucked sounds represent background galaxies, and cymbals represent foreground stars. In the Chandra sonification, wind-like sounds represent the neon purple X-ray cloud, and more compact background objects are presented as chirping birds!
Quelle: CHANDRA, NASA