Stellar, galactic and black hole

  • Astronomical data from three new objects has been translated into sound as part of a data sonication project.
  • The Chandra Deep Field, the Cat’s Eye Planetary Nebula and the Whirlpool Galaxy are the latest objects whose data has been turned into sounds.
  • The data comes from the Chandra X-ray Observatory as well as others NASA telescopes in space.
  • Data sonification allows users to hear and see information from cosmic objects.

This latest installment in our data sonication series features three different cosmic scenes. In each, astronomical data collected by NASA’s Chandra X-ray Observatory and other telescopes is turned into sounds. Data sonication maps the data from these space telescopes in a form that users can hear rather than just see, embodying the data in a new form without altering its original content.

Chandra Deep Field

This is the deepest X-ray image ever taken and represents more than seven million seconds of Chandra’s observation time. For that reason, and because the observed field is in the southern hemisphere, astronomers call this area the “Chandra Deep Field South”. At first glance, this image may seem like a representation of stars. Almost all of these differently colored dots are more like black holes or galaxies. Most of the former are supermassive black holes located in the centers of galaxies. In this data sonication, the colors dictate the tones as the bar moves from the bottom of the image to the top. More specifically, colors to the red end of the rainbow are heard as low notes, while colors to purple are assigned to higher ones. Light that appears bright white in the image can be heard as white noise. The wide range of musical frequencies represents the full range of X-ray frequencies collected by Chandra in this region. In the visual color image, this large frequency range had to be compressed in X-rays to be displayed as red, green, and blue for low, medium, and high energy X-rays. However, when sound is played, the full range of data can be experienced. As the piece scans up, the stereo position of the sounds can help distinguish the position of the sources from left to right.

Cat’s eye spray

When a star like the sun starts burning without helium to burn, it will blow off huge clouds of gas and dust. These eruptions can form spectacular structures like those in the Cat’s Eye nebula. This image of the Cat’s Eye contains both X-rays of Chandra around the center and visible light data from the Hubble Space Telescope, showing the series of bubbles that are ejected from the star over time. To listen to this data, there is a radar-like scan that moves clockwise from the center to produce pitch. Light farther from center will be heard as higher pitches, while brighter light is louder. The X-rays are represented by a louder sound, while the visible light data is softer. The round rings provide a constant buzzing, interrupted by a few sounds of spokes in the data. The rising and falling pitches that can be heard are due to the radar scan passing over the shells and jets in the nebula.

Messier 51

Messier 51 (M51) is perhaps better known by the Whirlpool Galaxy’s nickname because the orientation of its face to Earth reveals its coiled spiral arms. This gives telescopes here a view of another spiral galaxy similar to ours Milky Way, the structure of which we cannot perceive directly from our position in it. As with the Cat’s Eye, the sonication starts at the top and moves radially around the image in a clockwise direction. The radius is assigned to notes of a melodic minor scale. Each wavelength of light in the image obtained with NASA telescopes in space (infrared, optical, ultraviolet, and X-ray) is assigned a different frequency range. The sequence begins with sounds from all four types of light, but then moves separately through the data from Spitzer, Hubble, GALEX, and Chandra. At wavelengths in which the spiral arms are prominent, the pitches creep up as the spiral moves further from the core. A constant low hum associated with the bright core can be heard, interrupted by short sounds from dense light sources in the galaxy.

These sonications from the Deep Field, Cat’s Eye and Whirlpool star system were led by the Chandra X-ray Center (CXC). The collaboration was led by visualization scientist Dr. Kimberly Arcand (CXC), astrophysicist Dr. Matt Russo and musician Andrew Santaguida (both from the SYSTEM Sound project).