In the minutes before a solar eclipse plunged Chile into darkness, a loudspeaker projected a deep baritone to a group of blind men and women who had traveled to the Atacama desert to "hear" what hundreds of thousands of others had come to see.
Then, a moment of silence until the sunlight, and the sound, returned.
Tourists from around the globe converged on the northern Chilean desert on Tuesday to witness the total eclipse under the world's clearest skies.
University of Valparaiso
The musical experience, orchestrated by Chile's University of Valparaiso, was designed to help blind people, or those with some level of visual impairment, experience the phenomenon through a change in the frequency of sounds.
"It was exciting, incredible, a magical experience," said Octavio Oyarzún, 41, one of the thousands of people who came to the small town of Cachiyuyo, about 600 km (373 miles) north of Santiago.
A professor of music and blind from birth, Oyarzún traveled from the nearby port of Caldera to "listen" to the eclipse, the first in the region since 1592, according to Chilean astronomers.
"It's like a gift from science to be able to live this sensitive experience that we could not otherwise experience," added Oyarzún, who is married to a blind woman with whom he has two children who can see.
"I feel like a bridge to the unknown, something that makes it possible to translate into the world of sounds what would be a mystery to us," he added.
Lightsound "translates" light into sound
The sound-making device, called Lightsound, was developed by Puerto Rican astrophysicist Wanda Díaz Merced. It "translates" a greater amount of light into high-pitched sounds and greater darkness into bass sounds, Chilean astronomer Catalina Arcos told Reuters.
Arcos, a professor at the Institute of Physics and Astronomy at the University of Valparaíso, helped to organize the observation site in Cachiyuyo, a town of less than 300.
"This allows people who can't see the eclipse to hear it," said the scientist. "As astronomers, this excites us."
Denisse Reyes, 34, said the experience surprised her.
"I can perceive lights, I can recognize day and night, but this amazed me. I felt like I was entering the mysterious world of the planets and the solar system," she said.