People across the United States will be looking to the sky on Monday to witness a total solar eclipse. Others will be listening to it.

And to Harvard University astronomers working to transform the rare sight into sound, the eclipse should create a symphony.

鈥淲e mapped the bright light of the sun to a flute sound,鈥 said Allyson Bieryla, an astronomer at Harvard. 鈥淭hen it goes to a midrange, which is a clarinet, and then during totality, it kind of goes down to a low clicking sound, and that clicking even slows down during totality.鈥

The scientists designed a boxy device 鈥 a bit larger than a cell phone 鈥 that converts light into audible tones in a process called sonification. The sounds change based on the intensity of the light, allowing people with blindness or low vision to follow the progress of the eclipse.

The device is called a LightSound, and hundreds of them will be at eclipse-viewing events on Monday.

鈥淭hat image of totality is breathtaking and so it is visual, but that doesn鈥檛 mean that鈥檚 the only way you can interpret things or experience them,鈥 said Bieryla, who runs the LightSound Project. 鈥淎nd for someone without sight, they need a different sense to experience it.鈥

Solar eclipse 2024: LightSound device

Converting light into sound

The idea for LightSound was born during the last total eclipse in the United States in 2017. Bieryla started the project with astronomer Wanda Díaz-Merced, who experiences blindness and relies on similar technology to do her research. They created three prototypes 鈥 one in Jackson Hole, Wyoming, and two in Kentucky.

The current version of LightSound is the result of some tweaks and fine-tuning since those prototypes, but sonification has always been at the heart of it. The device uses a light sensor to take in data 鈥 in the case of an eclipse the data is light intensity, Bieryla said. Those numbers, the light intensity values, are then assigned an instrument sound using a MIDI synthesizer board in the device, she said. This allows the tones to change as the moon blocks the sun and Earth gets dark, so people with blindness can interact with the eclipse in ways they couldn鈥檛 previously.

Fast-forward to 2024, and the project has grown. Changes after the 2019 and 2020 total solar eclipses in South America, such as primarily using a printed circuit board instead of wires, made the device easier to build. With the help of local communities, the project was quickly able to scale up production, Bieryla said. The LightSound team hosts workshops in which anyone can learn to assemble a device.

鈥淚nstead of producing 20 in a day, we were producing 200 in a day, so it was a huge, huge improvement,鈥 Bieryla said, emphasizing that the community element is 鈥渨hat made this project successful.鈥

She said they built and distributed about 900 devices for the 2024 eclipse, which went to sites in Mexico, the United States and Canada.

Of those hundreds scattered across the United States, 29 devices were sent to Ohio state parks and wildlife areas that are in the path of totality. The Ohio Department of Natural Resources partnered with Opportunities for Ohioans with Disabilities, or OOD, to provide LightSound to dozens of eclipse-watch parties.

Bernadetta King, program manager at the OOD鈥檚 Bureau of Services for the Visually Impaired, said people are excited to be fully included at eclipse events 鈥 not in a separate place but immersed with everyone else as event organizers will plug the device into speakers.

鈥淪ometimes when you make something better for people with disabilities, you inadvertently make it better for everybody, so why don鈥檛 we just think that way to begin with?鈥 King said. 鈥淓ven the people that would be viewing the eclipse through glasses are hearing about this and say, 鈥極h, this is cool.鈥欌

King, who also experiences blindness, said she feels people with vision-related disabilities are not often top of mind. Devices such as the LightSound could also be an opportunity to keep pushing sonification technology in other ways, she said.

鈥淭his is kind of a foot in the door to open an area that has traditionally not been considered when you think about people who have blindness and vision impairment,鈥 King said, mentioning previous applications of sonification in weather, space and other science fields.

Other inclusive eclipse efforts

If you are not near an eclipse event that has a LightSound, the American Council of the Blind is hosting a virtual stream of the sound of various devices along the path of totality.

The Eclipse Soundscapes app is another resource for those who are visually impaired. The project, part of NASA鈥檚 Citizen Science initiative, will collect multisensory observations and recordings from people around the country.

In the app, there is a tool that uses vibrations and audio tones to convey each stage of the eclipse in addition to narrated descriptions. The project said the tool is 鈥渄esigned for you to hear and feel astronomical phenomena.鈥

Additionally, NASA partnered with the National Park Service and Earth to Sky on activities, including a webinar series to prepare interpreters for the event. National parks involved in the partnership will have elements for 鈥渢he blind and low vision, neurodivergent children, the physically impaired, and those with hearing impairments鈥 at watch parties across the country, the space agency said.

As for Bieryla and her team, there鈥檚 always another eclipse somewhere. Once this one is over, they will ship LightSounds to the next location. Because her small team can鈥檛 build devices for the whole world, the next goal is to teach people across the globe how to hold workshops. She said she hopes initiatives such as LightSound inspire young scientists.

鈥淚鈥檓 hoping that there is a blind child that maybe experiences this device and says, 鈥業 want to do astronomy,鈥欌 Bieryla said, 鈥渁nd we need to have those resources in place for that student to be successful.鈥