This Handheld Device Allows Blind People to Experience the Solar Eclipse With Their Ears

The technology, which translates the intensity of sunlight into a range of sounds, was designed to make eclipses more accessible to visually impaired people

A composite image showing multiple phases of an eclipse as the moon gradually covers the sun
A composite image showing multiple stages of 2019's solar eclipse as seen from Chile. Sebastian Brogca / Anadolu Agency / Getty Images

When a total solar eclipse crosses North America on April 8, many people will don eclipse glasses and stare up at the sky. But others will put on headphones: Researchers at Harvard University have developed a small device that will also allow blind or visually impaired people to experience the eclipse by listening.

The device, called Lightsound, receives light from the sun as an input and converts its intensity into musical tones. The project has a goal of distributing more than 750 free devices to groups hosting eclipse events.

“The sky belongs to everyone. And if this event is available to the rest of the world, it has to be available for the blind, too,” Wanda Díaz-Merced, an astronomer who is blind and is part of the LightSound team, tells Christina Larson of the Associated Press (AP). “I want students to be able to hear the eclipse, to hear the stars.”

The LightSound device “will actually give me more information than what I can possibly see with my eyeballs,” Yuki Hatch, a Texas high school student and astronomy enthusiast who is visually impaired, says to the New York Times Robyn Ross.

A total eclipse is more than just a visual experience—observers can feel the temperature drop as the sun is blocked out, and people have reported changes in the sounds of animals during totality. But the LightSound device will convert data from the sun into listenable tones, allowing people to hear the eclipse.

As the intensity of sunlight shifts, so will the sound played by the device. Flute tones represent bright light, clarinet notes evoke dimmer light and soft clicks mark the brief period of totality, National Geographic’s Stephanie Vermillion reported in January.

The researchers first developed a LightSound prototype in 2017 for that year’s total solar eclipse, which passed over the United States from Oregon to South Carolina. They had one device in Jackson Hole, Wyoming, and two more in Kentucky, at Morehead State University and the Kentucky School for the Blind.

The device was redesigned with improved sound quality for 2019’s eclipse in South America. The researchers distributed 20 devices across Chile and Argentina. During the pandemic, the project still managed to expand, with more than 100 devices sent to the two countries for another total eclipse in 2020. They can be attached to headphones or to speakers, which can allow large groups of people to listen in on the data.

Next Monday’s total eclipse will first make landfall at around 11:07 a.m. Pacific time along Mexico’s western coast. Over the next couple of hours, the eclipse will trace a path of totality to the northeast over North America, eventually reaching the Atlantic coast of Newfoundland, Canada.

Every state in the contiguous U.S. will be able to experience at least a partial eclipse. Only observers in the path of totality will be able to experience the moon completely blocking the sun, darkening the sky and making the sun’s outer atmosphere, or corona, visible.

In advance of the upcoming eclipse and the recent annular eclipse in October, the LightSound team held workshops at locations including Harvard University, the University of Texas at Austin and the University of Texas at San Antonio, where volunteers built devices to be donated.

“That’s been heartwarming to me—just the amount of work that people have given to this project and the excitement around it,” Allyson Bieryla, a Harvard University astronomer and part of the LightSound team, tells the New York Times.

The LightSound website also has instructions for building the devices offered in English, Spanish and French.

This year, the team received more than 2,500 requests for devices, per the New York Times. They have sent devices to many locations across North America, including over half of the states in the U.S., as well as locations in Puerto Rico, Canada, Honduras and Mexico. For those that do not have access to a device in-person, the Perkins Library of the Perkins School for the Blind in Massachusetts will share the sonification over Zoom, according to the AP.

The LightSource devices are part of a wider movement to make astronomy less reliant on purely visual information. Researchers at NASA have translated data from telescopes into musical sounds. And scientists have made books with textured graphics that teach people how eclipses work through touch.

“Eclipses are very beautiful things, and everyone should be able to experience it once in their lifetime,” Hatch says to the AP.

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