Stargazers Scan the Universe at Public Astronomy Night in Dartmouth
At dusk on a recent Saturday, Professor Alan Hirschfeld and one of his grad students calibrate the large telescope inside the UMass/Dartmouth observatory. They’re setting up for a public astronomy night, a monthly event the University co-hosts with the Astronomical Society of Southern New England, or ASSNE. Hirschfeld said the telescope was designed and built by UMass students in the 1980’s, and went online in the early 90’s. It has a 16-inch diameter, or aperture.
“So the bigger the aperture, generally the more light the telescope can collect, and the fainter the objects that it can see,” said Hirschfeld.
The observatory sits at the far corner of a field, to eliminate as much light from the campus buildings as possible. It’s used mainly by UMass physics students, and those taking astronomy classes. But tonight, it’s open to the public.
The observatory has the familiar dome with a slit for the telescope to look through. When it needs to be rotated, the dome rolls on heavy-duty garage door wheels that are activated by four motors. The telescope’s position is separately controlled by a hand-held computer device.
“So this has a memory which is filled with the locations of many thousands of celestial objects, including the planets,” said Hirschfeld.
Tonight, visitors get to view Jupiter. Hirschfeld’s grad student, Brian Pinault, keys in the pre-programmed coordinates, and the telescope begins to rotate. Then, Hirschfeld reaches for an eyepiece and fits it onto the lens.
The huge planet is clearly visible, along with two of its four brightest moons, which Galileo discovered in 1610. Although they look deceptively close in the lens, these objects are 500 million miles away. Hirschfeld said part of the excitement of using the telescope is knowing what you’re looking at.
“So if you’re looking at what you know to be a distant galaxy, even if it’s just a little smudge of light to the eye through the telescope, just knowing that there may be hundreds of billions of stars in that little faint glow – that in itself is very satisfying,” Hirschfeld said.
And he loves sharing that excitement with others, like Fall River resident Sam Sutter and his 10 year-old daughter Ava, both of whom get a good look at the faraway planet.
Outside, ASSNE members have also set up their own telescopes alongside their cars nearby – a sort of astronomy tailgate party – and they’re more than willing to let visitors have a look through their lenses. Club member Rebekah Bartlett from Foxboro said many members build their own equipment.
“Some of the biggest scopes are homemade scopes, too,” she said. “You can obtain mirrors on your own, you can grind your own mirror. You can build your own equipment if you’re interested in doing that.”
One of those do-it-yourselfers is Jerry Trahan from Rehoboth. He said he was retired and looking for a new activity.
“And then I found there was an astronomy club practically in my back yard,” Trahan said. “So I joined, and I learned about the various telescopes. And just by chance, somebody gave me some parts from an old telescope, and I found a book on how to make them, and looked through it and decided to give it a try. Six months later, I have it.”
Jerry’s expecting this to be a long night.
“If it’s as good as it looks, I might be here til dawn. I’ve had some sessions where you go over to a friend’s house, we set up the telescopes, the wife would come out and get interested, and before you know it, the sun’s coming up,” Trahan said.
He easily points out various celestial landmarks: the Big Dipper, the North Star, Polaris, the Constellation Orion, and the Horsehead Nebula.
Nearby is another ASSNE member, Pete Peterson from Barrington, Rhode Island. He points out Sirius. He said it’s the brightest star in the northern hemisphere because it’s only 21 light years away.
“Now if you look at Orion over there, and had you been looking at the second star right in the middle of the Orion sword…you can see the belt going one, two, three across…you look down one, two, three below the belt, you see a sword hanging,” said Peterson. “And that middle star isn’t a star at all. It’s a roiling cloud of stardust that’s being illuminated by several bright stars right in the heart of that nebula. And that’s actually a star nursery. Stars are being formed from that stardust as we observe it right now. And the light that left that particular object left there back when Arthur was the King of England.”
Back at the observatory, there’s a steady stream of visitors lining up at the doorway. Julia Ryan just viewed the moon through the 16-inch telescope.
“I’ve seen it from far away so many times, but it’s so awesome to see it up close. It really is a different perspective. It makes you feel really small. But it makes you realize how large the world and the universe is,” said Ryan.
It’s not exactly a typical weekend leisure activity – wandering around a pitch-black field looking through telescopes. But on this perfectly clear Saturday night, these curious visitors have gotten a chance to see the infinite universe as they rarely do - up close and personal.