Winter is the time for stargazing. The skies tend to be clearer, more often during the winter. “Because the air is cooler, it can’t become saturated with moisture as happens in the warmer months,” said Alan Hirshfeld, professor of physics and astronomy at the University of Massachusetts Dartmouth. “There’s a definite advantage to observing the stars in the winter in New England. The skies are generally clearer.”
With the stars shining so bright, it’s well worth the effort of bundling up and braving the frigid temperatures. And it merits regular outings, too, as the view is ever-changing. “People have the impression that astronomy is about looking up at the sky where nothing ever changes, but the truth is that it is changing all the time, sometimes within just a few hours,” said Dipankar Maitra, professor of astronomy at Wheaton College.
Professor Hirshfeld agrees. “After you find an object in the night sky, remind yourself to go look for that thing in an hour and you’ll see that it’s moved. There’s this hidden world that is just so obviously there on every clear night,” he said. “The realization that the night sky is not static is really inspirational. Something is happening up there. That ties you right back to the first humans who knew the night sky a lot better than we do.”
Learning to see
One of the great things about stargazing is just how accessible it can be for those who are new to it. You don’t need a fancy telescope and lots of equipment. In fact, newcomers will do best to avoid telescopes altogether and start out with “naked eye” observing. Telescopes require some knowledge and time to set up correctly, and using a telescope can make finding objects harder due to the narrow field of vision. If you want to enhance your vision, binoculars are a good place to start.
“When people ask for telescope recommendations and they are new to astronomy, I actually recommend that they start out with a good pair of binoculars, which can also be used for other pursuits, such as birding,” said Regina Jorgenson, director of astronomy at the Maria Mitchell Association on Nantucket. “You can actually see a lot. You can see the moons of Jupiter; you can see the rings of Saturn with a good pair of binoculars. It’s amazing what you can see with binoculars and you don’t have the setup issues that come with telescopes.”
The most important factor in stargazing success is selecting a site with dark skies. You will have the most success in seeing the stars and other celestial objects from little to no light pollution. Fortunately, the Buzzards Bay watershed region offers plenty of nearby choices, even if you live in downtown New Bedford or Falmouth.
Patience is also required. When you step outside into a dark location, you need to give your eyes time to adjust. It takes at least five minutes, though you will have better results if you wait for twenty minutes or more. And during that time, you want to avoid reading email or looking at your smartphone, as its light will counteract your eyes’ adjustment.
The only problem with not looking at your smartphone is that you may want an app that helps to guide your stargazing. There are many, and they can be useful. Jorgenson recommends Sky Guide (iOS) and Stellarium Mobile Sky Map (Android) as her favorites. And if you are going to use those, she also suggests that you become familiar with how to turn on the red light filter on your phone, which will reduce its impact on your night vision. As an alternative, Maitra said Sky and Telescope magazine interactive skywatching tools offer great value and can be accessed for free from a desktop or laptop before going outside.
Having an expert guide to stargazing helps, too. The Buzzards Bay Coalition regularly offers stargazing events led by knowledgeable volunteers from the Astronomical Society of Southern New England. (Check the events calendar for upcoming programs.) You also will find regular observatory open house nights at the University of Massachusetts Dartmouth, Wheaton College in Norton and the Maria Mitchell Association on Nantucket. [Note: Social distancing has closed all three observatories’ open house programs for the moment, but you can register for virtual stargazing sessions with the Maria Mitchell Association. —Ed.]
What to see
Stargazing can be something of a treasure hunt. The winter season brings a variety of astronomical events. Planets rise above the early evening horizon with piercing brilliance, tiny bits of meteoric dust streak in flames across the sky, and constellations march in procession through the night.
Stories in the sky. For many people, the constellations are the first thing that come to mind when thinking about stargazing. And for good reason, the characters and their stories are easy to remember, and every culture has its own set of myths associated with the patterns that people have seen in the sky. In addition, the constellations provide a roadmap for identifying celestial objects–what astronomers call star-hopping.
In winter, the “star” of the constellations is Orion the hunter, which rises in the East several hours after sunset. The most notable part of the constellation is Orion’s belt, the three medium-bright stars at its middle. In fact, Orion’s two brightest stars–Betelgeuse and Rigel–lie at opposite corners of the starry rectangle that encloses the belt.
Also in the Orion constellation is another object that is not a star at all: the Orion nebula, which is located in the middle of the sword that appears to hang from the hunter’s belt. “It would probably look to most people like a faint smudge but it’s actually the tremendous clouds of gas and dust that are the birthplace of stars,” Jorgenson said. “So, it’s where the hot, young new stars are being born.”
Once you’ve found and admired Orion, you can move on to find the adjacent constellation Taurus the Bull and the star cluster Pleiades (or Seven Sisters) by shifting your gaze up higher into the night sky. Or wait a little while and look back to the East, and you will see Orion’s faithful dogs Canis Major, with its brilliant star Sirius, and Canis Minor rising into view.
In addition to the winter constellations, Hirshfeld said that early winter distinguishes itself in that observers are still able to see some of the star patterns associated with summer. Most notably, he said, you can view the Summer Triangle—composed of Altair, Deneb, and Vega, each of which is the brightest star of its constellation (Aquila, Cygnus, and Lyra, respectively)—on the western horizon.
Star showers. The Perseid meteor shower of August may be the most-viewed and well-known, but December brings its own season of shooting stars—the Geminid meteor shower, which typically peaks during the middle of the month. The glowing streaks of the Geminid meteor shower are often bold, white and bright. And on a dark night, you might catch 50 or more meteors per hour. While the greatest number of meteors typically fall in the wee hours after midnight, this year’s Geminids are expected to start during the mid-evening.
This year, the Geminid display is expected to be particularly good because it will hit its peak—December 13 and 14—during the new moon, when the night sky is exceptionally dark. So, if the skies are clear, it should be worth your while to head outside to catch the show.
A galaxy far, far away. From an interstellar perspective, virtually everything we see in the night sky is a “neighbor.” In other words, it’s part of the Milky Way galaxy, which is home to our solar system. For naked-eye observers in the Northern Hemisphere, there is exactly one exception to this rule: the Andromeda galaxy. (The Large and Small Magellanic Clouds stand out boldly in the night sky of the Southern Hemisphere.)
“Probably my favorite thing to look for, and I love to point this out to people when we have open observatory nights in the fall and winter, is the Andromeda galaxy,” Jorgenson said. “It’s the only thing you can see [in the Northern Hemisphere] with your naked eye that is outside of our galaxy. Everything else that you see in the night sky—all the stars, all the planets—is in our Milky Way galaxy. … It’s 2.5 million light years away.”
However, the Andromeda galaxy is not that easy to find. “You can only see it when the sky is very, very dark. If the moon is out, you won’t be able to see it,” she said. The galaxy appears in the night sky below the constellation Cassiopeia, which is shaped like a “W.” The deeper “V” shape in the “W” essentially serves as an arrow pointing to Andromeda. Jorgenson suggests that, once you’ve identified the area where it should appear, it’s best to look slightly to the side, allowing your more sensitive peripheral vision to spot the far-off galaxy first before attempting to look more closely.
Meeting of the planets. While it doesn’t happen every winter, or even every year, December 2020 offers a spectacle that will not occur again for 60 years: the conjunction of Jupiter and Saturn. A conjunction happens when the planets’ respective orbits briefly bring the two bodies into alignment, at least from our perspective here on Earth. Right now, the two giant planets are moving toward each other in the sky. The last time a similarly close conjunction occurred was in the year 2000. It will not happen again until March 15, 2080.
Already, Jupiter and Saturn are close together in the southern part of the sky; eventually they will appear to merge. Their orbits will briefly bring them into alignment on Monday, December 21, at which point they may appear to be one exceptionally bright object in the western sky, just after sunset. Shortly after that date, the two planets will appear to be moving apart, but remain visible for the rest of 2020.
Where to go
As with real estate, location matters when it comes to stargazing. Depending on where you live, you may be able to see some or all of the night sky from your own yard or neighborhood. If not, the Buzzards Bay watershed region boasts numerous locations that offer broad open vistas and dark skies. Here’s a short list for consideration.
[Please note: Massachusetts is currently under a stay-at-home advisory that prohibits travel outside the home from 10 p.m. to 5 a.m. —Ed.]
East Beach (Westport). This town beach offers sweeping views out over the water, from the East to the Western horizon, with very little artificial light to interfere.
Apponangansett (Dartmouth). You will find a good deal of open sky in all directions here, although interference from artificial light sources could be an issue in some directions.
East Beach (New Bedford). For a city location, you will find pretty good viewing options here, particularly looking toward the southeast.
The Bogs (Mattapoisett). Dark skies abound here. If you walk just a little ways from the parking area, you will find good views in all directions.
East Over Reservation (Rochester) The expansive, open fields here are just steps from the parking area and offer dark skies in every direction.
Little Harbor Beach (Wareham) This town beach offers incredible views of the night sky in every direction, but a town sticker is required.
Wood Neck Beach (Falmouth) The bay views and the salt marsh surrounding this spit of land provide another spot for 360-degree viewing.