Solar telescope offers chance to stargaze

Katelyn Eaman can appreciate the power of the sun better than most.

The geology graduate student researches how Mars’ now-barren landscape was carved and transformed by ancient waterways. That water doesn’t exist today because Mars lost the magnetic field necessary to protect itself from the sun’s radiation, which eventually stripped away the planet’s atmosphere and its ability to retain liquid water.

So Eaman also appreciated the chance to see our nearest star through the lens of a solar telescope recently at the Department of Earth Sciences’ welcome back picnic outside Cooke Hall.

“I’m very thankful that our department has the ability to acquire something like this, and share it, too,” Eaman said. “It’s not as if it’s sequestered away in one person’s lab. It’s for everybody.”

The solar telescope will be in the spotlight more often, as the department plans student and community events to highlight its ability to observe the sun and our other celestial neighbors.

It was used to observe last year’s total solar eclipse from Lake Erie State Park by Beata Csatho, professor of earth sciences. She led one of 35 teams positioned along the path of totality as part of the Citizen Continental-America Telescope Eclipse (CATE) project, funded by NASA and the National Science Foundation. The goal was to use telescopes to collect polarized images of the Sun’s corona, its outermost atmosphere — something only possible during an eclipse.

“After the eclipse, NASA allowed us to keep our telescope as long as we promised to use it for education and outreach, so that’s exactly what we’re doing,” Csatho said. “I plan to use it in my teaching and also some events where we can engage the community.”

Unlike ordinary telescopes used for viewing distant stars, solar telescopes are specialized to handle the immense brightness of the Sun. It’s equipped with a detachable filter that can dim down the brightness by a factor of tens of thousands and protect both the observer’s eyes and the telescope’s internal optics.

Instead of an eyepiece, the view is displayed on a connected laptop. A digital camera first captures the Sun’s image, allowing it to be stored while also measuring the light’s intensity in different wave orientations. Such images can reveal details of the corona, including its magnetic connectivity and solar winds.

The computer also helps the telescope automatically reposition itself to track the Sun in real time.

“So long as you input the declination of the telescope, the computer can compensate for the rotation of the Earth and keep the sun centered in the field of view,” said Nicholas DiFrancesco, assistant teaching professor in the Department of Earth Sciences.

We’re currently in the midst of a solar maximum — the peak of the sun’s 11-year magnetic cycle, when its magnetic field is at its strongest. This heightened activity can produce dazzling auroras but also disrupt satellites, communication systems and power grids.

“There’s so much about the sun that affects our planet and our entire solar system, so being able to make that more real for students, I think, is a big deal,” DiFrancesco said.

Csatho agreed. She and other researchers in the department typically rely on satellites, laser pulses and other remote-sensing technology to observe the geological features of the Earth, the moon and Mars.

Thus, the telescope offers something a bit more tangible. 

“It’s nice to have equipment that the students can actually touch with their own hands,” she said, “and an image of our solar system that they can see with their own eyes.”