Movie actors Tom Cruise, Meryl Streep and Denzel Washington are Hollywood box office heavyweights. But if you want to view real stars on a really big screen, head to the North Museum's planetarium.

"It's really nice to see when people get really excited for it," said Cole Penkunas, who's been the North Museum's resident astronomer for two years. "It gets me really excited when people ask questions. It shows me they're interested in science and astronomy. They're excited about something I'm excited about."

Simply put, the planetarium is one of the most popular attractions at a place - the North Museum of Nature and Science, located at 400 College Ave., Lancaster - that has so many interesting exhibits to experience. Admission to the planetarium, which offers shows mainly on Saturdays and Sundays at 11 a.m. and 2 p.m., is included with admission to the North Museum.

"For me, there's definitely a coolness factor to it," said Penkunas. "I think some of it is because we want to know where we exist in the universe. Astronomy can tell us a lot about physics, about the Earth and the nature of reality on a really big scale. I think astronomy just being the study of the stars is just very appealing to a lot of people. A lot of people want to explore the world. Earth has been well charted, and now people are looking up for new stuff."

The unidirectional planetarium at the North Museum is physically made up of 70 seats and a 40-foot-diameter dome. A projection system uses special lenses to portray images of stars, galaxies, moons, constellations and other celestial bodies on the auditorium's ceiling.

"It's more of a traditional movie-style planetarium where everyone faces the same way," said Penkunas, a resident of Lititz. "The main thing with the planetarium is to get more space education out there. The goal is to educate about space and stars in fun and immersive ways."

Based on a rotating schedule, the planetarium offers about 15 to 20 different shows for adults and kids throughout the year, including "Night Sky Tours" and other seasonal presentations. That's a total of more than 240 of the 30- to 40-minute presentations annually.

The planetarium also periodically offers shows on dinosaurs and super volcanoes, as well as select documentaries.

"I think we have a really good understanding of our solar system as it exists now," said Penkunas. "We have a good understanding of the sun. But there are still a lot of questions. We have a really good idea of how planets formed, but we don't know a lot of the specifics. We know a lot more than we ever did before, but a lot of the exact mechanisms of astronomy are still very much being researched. Overall, there's still a lot to learn."

The North Museum's planetarium receives more than 2,500 visits each year. Some come from curious out-of-town tourists, but mainly they are from Lancaster County adults and students who want to learn about other worlds, as well as the world around them.

"A lot of times it's people who have never been to a planetarium before," said Penkunas. "They hear there's a planetarium, and they get excited. A lot of people come here just for the planetarium. Planetariums aren't super common, and they aren't easy to find."

"I always want people to think astronomy is cool and accessible," continued Penkunas. "Space is far away, but we're not far away. I think it's important for people to have an interest in astronomy."

The planetarium, which was built in the 1960s and renovated in 2012, is located on the main floor of the three-floor structure that houses the North Museum of Nature and Science. The planetarium is surrounded by 12 main sections, each featuring its own themed exhibits, displays and collections.

"I'd say that the planetarium is a companion to the rest of the museum," said Penkunas. "It's one of the ways we drive people to come here. There are two main features; the first is the rest of the museum and the second is the planetarium. It's one of the main features."

For additional information, go to http://www.northmuseum.org.