On Monday, when the moon passes between the sun and the Earth and causes a total solar eclipse, more than 30 million people across the United States will be under the moon’s shadow for the otherworldly experience. But the cosmic spectacle won’t just be an awe-inspiring sight; it will also be an opportunity for members of the public to get involved in cutting-edge science. From using a smartphone app to help create a movie of the eclipse to gathering information about the shape of the sun and cloud coverage on Earth, ordinary people with no experience in astronomy can become a scientist for a day.
Despite our sun’s constant presence, remarkably, its precise shape is not known.
Despite our sun’s constant presence, remarkably, its precise shape is not known. A free phone app called SunSketcher will let volunteer observers along the eclipse’s path of totality — the thin region where the sun is completely blocked out — capture their views of the rare astronomical event. Researchers hope studying the images taken with these ubiquitous devices will reveal the last drops of sunlight, also known as Baily’s beads, that pass through the valleys on the moon’s surface just before and after totality.
“You only need one piece of equipment, and that’s your phone,” Gordon Emslie, a professor of physics and astronomy at Western Kentucky University and leader of the SunSketcher project, told me.
“Because we know the exact shape of the moon, the timing of when those beads flash on and off gives us very precise information on the shape of the sun in the background,” Emslie added.
He encourages project participants to start the app and prop up their phones facing the sun at least five minutes before the moon masks the Sun so as not to interrupt their overall eclipse viewing experience. The app will handle the rest.
Patricia Reiff, an astronomy professor at Rice University, is the southwest regional director for Citizen CATE, a participatory science project that will have volunteers operate a series of telescopes with polarized cameras stationed in 35 observing locations along the eclipse’s path. The goal: to document the appearance and light behavior of the corona — a wispy halo of plasma around our star that’s hard to study from Earth.
The project is a rerun of one that occurred during 2017’s total solar eclipse, shortly before the solar minimum, that is, when sun activity was at its lowest. This time around, sun activity will be approaching a major peak, giving researchers insights into how the corona varies across the solar activity cycle.
Many participants from 2017 will also be part of this year’s observations. “We are working with amateurs, high schoolers and especially people of color,” Reiff said. “Trying to get people who never really considered a science career before excited about science is a big part of the project.”
Another photo-taking project, the 2024 Eclipse Megamovie, involves more high-tech equipment. Volunteers will use a DSLR camera and an equatorial mount (to compensate for Earth’s rotation) in order to crowdsource more than 1,000 high-quality images of the eclipse, which will then be stitched into a movie. In particular, scientists in this project want to gain insights into solar jets, bubbles of plasma that flow out of the sun.
“One of the things we’re interested in is how things propagate away from the sun and into the solar system, interacting with nearby planets like Earth,” Laura Peticolas, associate director of the education and public outreach group at Sonoma State University and leader of the Eclipse Megamovie project, told me. Eclipse viewers both inside and outside the path of totality can also help scientists track environmental changes during Monday’s eclipse. Eclipse viewers both inside and outside the path of totality can also help scientists track environmental changes during Monday’s eclipse. Using an eclipse tool in the GLOBE Observer app and a thermometer, participants can record shifts in air temperature and clouds in order to understand how eclipses affect weather patterns. “Because the eclipse changes the solar energy right in the location where you’re observing, it’s going to potentially affect cloud cover and temperature,” Holli Riebeek Kohl, GLOBE Observer lead at NASA’s Goddard Space Flight Center, told me. Volunteers for these sorts of community science projects are often excited to be part of something bigger, Riebeek Kohl added: “A lot of people have indicated they wanted to contribute to science so that their experience is more meaningful.” As Reiff said about the oncoming eclipse, “It’s the most adrenaline you can have without being actually in physical danger.”
Paola Rosa-Aquino
Paola Rosa-Aquino is a freelance journalist covering science, space and the environment. Born and raised in Puerto Rico, she now lives in Brooklyn, New York, with her canine co-worker Cece. 
