Chandra Communications and Public Engagement

K. Arcand, P. Edmonds, K. Lestition, M. Watzke

The Chandra Communications and Public Engagement program consists of two strands, the press efforts and the public engagement efforts such as our participation in the Red Sox STEM Days, Astronomy on the Mall, the World Science Festival, the Cambridge Science Festival and other public events. We also produce materials for use by the general public and have developed a number of materials for “at home” use during the pandemic.

In addition, as we explained in an earlier article, the “education” portfolio was removed from mission programs and replaced, 5 years ago, by the “Science Activation” program managed out of SMD at NASA HQ. Chandra’s role in this latter program is as a Co-I in the Universe of Learning (UoL), program, with PI STScI and other Co-I’s JPL and IPAC along with additional partners. NASA’s UoL program is mandated to focus on “informal education”, that is, not in the classroom but in after-school, summer, museum, and other non-classroom venues, and to encompass in its programs, the application to the informal education ecosystem, the science of all of the astrophysics missions. The Science Activation program strives to enable NASA science experts and to incorporate NASA science content into various learning environments effectively and efficiently for learners of all ages.

Because of social and cultural issues that have become prominent during the last year or so, NASA has requested that all of us be aware of socially, culturally and ethnically offensive language whether in social media or simply in nicknames given to astronomical objects. And in its outreach and education programs, NASA has also specifically emphasized programs and products that acknowledge goals of diversity, equity, inclusion, and accessibility (DEIA) as well as utilizing new technologies. Chandra has pioneered a number of such programs.

Following is the first of what will be a multi-part series of articles by the Chandra Communications and Public Engagement group describing some of these projects. To become involved in this or any other of our projects, please contact


Over the years, the Chandra Communications and Public Engagement group has continually explored new ways to engage with all elements of the public. We have pioneered programs in 3D printing of astronomical sources, tactile and Braille resources, in presenting astronomical sources in VR, AR and hologram applications. The sonification project – that is, translating data into sound – dovetails well with our group’s central tenant to bring X-ray astrophysics to the widest possible audiences, including underserved communities such as people who are blind or low vision.

The sonification project started with a collaboration between the CXC’s visualization scientist Kim Arcand, and astrophysicist Matt Russo and musician Andrew Santaguida, both of the SYSTEMS Sound project. Because the program also fit well with the goals of NASA’s UoL program, the trio also collaborated with relevant UoL programs.

“When we came up with the idea for the sonification project,” said Arcand, “it seemed like it could be an exciting way to do something with Chandra data that had not been done in such a way before. Part of our mandate being part of UoL is to put Chandra data into context with other missions such as Hubble, Spitzer, and other astrophysics missions, while creating new pathways to reach people.”

The first phase of the sonification was released in September 2020. It included three of Chandra’s most popular images translated into sound: the region around Sgr A*, Cas A, and the “Pillars of Creation” in M16.

In the Sgr A* piece, the translation begins on the left side of the image and moves to the right, with the sounds representing the position and brightness of the sources. The light of objects located towards the top of the image are heard as higher pitches while the intensity of the light controls the volume. Stars and compact sources are converted to individual notes while extended clouds of gas and dust produce an evolving drone. The crescendo happens when we reach the bright region around Sgr A* to the lower right of the image. Users can listen to data from this region, roughly 400 light years across, either as “solos” from Chandra, Hubble, or Spitzer, or together as an ensemble.

In addition to the Galactic Center, this project has also produced sonified versions of the remains of the supernova Cas A, and the “Pillars of Creation” located in Messier 16. In Cas A, the sounds are mapped to four elements found in the debris from the exploded star as well as other high-energy data. The distribution of silicon (red), sulfur (yellow), calcium (green), and iron (purple) are revealed moving outward from the center of the remnant, starting from the location of the neutron star, in four different directions, with intensity again controlling the volume. There is also another version with fifth audio path moving along the upper left jet.

In the “Pillars of Creation” piece, the sounds are generated by moving horizontally across the image from left to right as seen in both optical and X-ray light. As with the sonification of the Galactic Center, the vertical position of the recorded light controls the pitch, but in this case it varies over a continuous range of pitches. Particular attention is paid to the structure of the pillars which can be heard as sweeps from low to high pitches and back. The two different “melodies” of optical and X-ray light can be enjoyed individually or simultaneously.

In the short period of time the innovative project has been available, there has been a surge of millions of hits to the materials on the website, millions of views of the videos and tens of thousands of likes on social media platforms. In the coming weeks and months, additional examples of sonified data from Chandra and other telescopes will be added for the community. Please visit the Universe of Sound website, which will serve as a repository for all of the related materials. And please contact any member of the team if you have a source or sources that you think would lend themselves to either 3D, VR, AR or sonification. We rely on collaboration with scientists to develop products with scientific accuracy and integrity.