During 2017’s partial solar eclipse — when the moon obscured part of the sun — educator Rob Hanson set up a telescope at Marsh-Billings-Rockefeller National Historical Park in Woodstock.

He was impressed by the crowd.

“There’s probably over 100 plus people, a long line, some people waited 20 or 30 minutes then got back in line for another view,” he said. “That part for me was special.”

He’s looking forward to a similar experience Monday when the Twin States will be in the path of a total solar eclipse. Being in the path of totality — or near totality, as is the case in much of the Upper Valley — could be once-in-a-lifetime event.

NASA describes a total solar eclipse as a “cosmic coincidence,” which happens when the moon passes between the sun and earth, casting a shadow on earth that obscures the sun — creating mid-day darkness. They happen only occasionally because the plane of the moon’s orbit does not precisely align with the planes of the sun and the earth.

A total solar eclipse won’t be seen again in North America for more than two decades, according to NASA. The last time a total solar eclipse was visible in New Hampshire skies was 1959 and another one won’t be here until 2079, according to the New Hampshire Department of Business and Economic Affairs, Division of Travel and Tourism Development. In Vermont, the last total solar eclipse was in 1932, according to reporting from Vermont Public.

Throughout the Twin States, tourism officials are preparing for thousands of people to descend. Businesses are selling eclipse-themed items. People are looking for glasses to protect their eyes when they look to the sky on Monday.

The eclipse is expected to hit the region at about 2:15 p.m. on Monday, with totality about 15 minutes later and expected to last about three minutes. A partial eclipse is expected to last until about 4:40 p.m.

The event is of particular interest to Upper Valley space enthusiasts such as Hanson.

“From everything I’ve read and all the people I’ve met, they say the same thing over and over,” said Hanson, who serves as co-director of Horizons Observatory at The Prosper Valley School in South Pomfret. “You don’t know an eclipse until you experience a total eclipse.”

Looks of awe

Hanson has largely learned about astronomy on his own through what he calls “armchair astronomy” and living in the Upper Valley plays a role in that interest.

“I think just the experience for everyone, especially in New England where there’s not a lot of light pollution, you get outside and look up into the Milky Way and you realize there’s a lot more to life than what we live and what we experience here,” Hanson, of Woodstock, said. “Diving deeper into that became a little bit of a passion of mine through the years.”

Hanson retired around a year and a half ago from The Prosper Valley School after more than four decades as an educator. Since then, he has continued to teach students through activities at the Horizons Observatory, located at the school.

During programs at the observatory — including public observation nights — Hanson tries to keep a sense of wonder at the forefront. As the eclipse nears totality, he will be looking both up and around.

“From what I understand, it’s as fun to watch people’s reactions” to the eclipse, as it is to watch the eclipse itself, said Hanson. “Those types of strong feelings and emotions, you don’t have to know all the geometry and science behind what’s going on, although I think it’s helpful.”

A beautiful experience

Another person who shares Hanson’s enthusiasm for star gazing is his former student, Aidan Keough-Vella, who saw 2017’s partial eclipse when he was living in Florida.

Keough-Vella, now a junior at Woodstock Union High School, has always been drawn to the stars. He really started to explore the power of the cosmos when he was in sixth grade at the Prosper Valley School.

That was when, under the tutelage of Hanson, Keough-Vella did a year-long project about the birth of stars using resources — including multiple telescopes and an astrophotographic system to take pictures of celestial bodies — at the Horizons Observatory. Now a junior at Woodstock Union High School, he attributes the origins of his plan of pursuing aerospace engineering to that sixth grade project.

“It kept my interest alive through the years,” Keough-Vella said of the observatory. He’s also a volunteer docent there and he works with Hanson and others to inspire that interest in the stars.

“I think the fact that we have this moment of totality with the eclipse that’s so close to home is really exciting,” Keough-Vella said. “Events like this don’t come by every day.”

He will be traveling to Cape Cod, Mass., with his family for spring break and view it from there.

“I think it’s fun to tell a story about how you got to see an eclipse, but I think it’s going to be a truly beautiful experience to be there, seeing it with your own eyes rather than on a phone or online,” said Keough-Vella.

Inspiring the next generation

Major astronomical events have a way of pulling people together. In 2017, Tara Tomlinson was living in Colorado and saw firsthand how much viewing the eclipse meant to people.

“Just hearing the collective gasp when it finally hits … seeing the excitement and wonder. Everyone’s faces light up,” said Tomlinson, who now is pursuing her doctorate at Dartmouth’s Thayer School of Engineering and works for NASA. “It’s just whole groups of people being really excited and interested. That’s really cool.”

Part of the appeal of eclipses is that people of all ages can relate to the sun and the moon, Tomlinson said. Then, they might be encouraged to dive a little deeper.

As a planetary scientist one of Tomlinson’s favorite things is to share her knowledge with the public.

“I didn’t have female science role models when I was a kid. I never saw people like me,” Tomlinson said. During Monday’s festivities, she is looking forward to talking to kids about the science behind their excitement. A big cosmic event like an eclipse could perhaps spark an interest that could lead to a lifelong passion or career like the one Tomlinson has.

“I think it’s really important to be there as someone they can look at,” she said.

Tomlinson will be at Thetford’s Latham Library the day of the eclipse instead of traveling farther north for complete totality. She wants to experience the eclipse with her community — especially its youngest members.

“Just having a big deal like this in our little town and our little state is really exciting for people,” she said. “They get really excited to learn about it too.”

Community-wide events

Many town officials — particularly those in recreation departments and libraries — are working together to host free community viewing events.

“There’s not a lot of events that touch everybody this way,” said Nancy Fontaine, adult services and technology librarian at the Enfield Public Library.

The library is temporarily located in a building on the former La Salette Shrine — now owned by the Enfield Shaker Museum — while Whitney Hall is being renovated. On Monday, staff will host an eclipse viewing event with the town’s recreation department.

There will be solar and moon-themed games in addition to snacks such as moon pies and Sun Chips. Library staff have also been distributing 500 eclipse-viewing glasses they got for free from the Space Science Institute, a nonprofit organization that launched a program to distribute glasses produced by the National Science Foundation to libraries.

“Word got out in the community and people have been coming in,” Fontaine said. In the lead up to the eclipse, library staff also have been hosting eclipse-related programs. Last month, Grafton resident and astronomer Rick Fienberg gave a talk that was well attended by community members. They put out a moon-themed community jigsaw puzzle.

“It’s actually very hard,” Fontaine said. “We don’t know that is going to be done by the eclipse.”

They’ve also posed a question to the library’s youngest patrons: Do they prefer the sun or the moon?

“The kids love this,” Fontaine said. “The moon won.”

In Windsor, Assistant Town Clerk Riley White has been working with the Recreation Department on an eclipse viewing event near the town recreation center. There is another gathering taking place at the library.

“I think it’s super exciting to be in the midst of it,” White said.

Liz Sauchelli can be reached at esauchelli@vnews.com or 603-727-3221.