Binoculars for Astronomy and Stargazing: Part 1

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The night sky is filled with wonders—so many that we humans build multi-billion-dollar telescopes to study them. The good news is that a lot of these wonders are available to all of us as we stargaze in our own backyards, and the easiest, fastest, and most convenient way to start exploring these is with a pair of binoculars. Even better, you don’t need to get your hands on an expensive pair of dedicated astronomical binoculars to start enjoying the night sky.

In this first chapter of a three-part series, we talk about the advantages of binoculars for night sky viewing and discuss the different things you can see with your binoculars. In Part 2, we get into the details of what makes a good binocular for astronomical use and finally, in Part 3, we discuss some recommended binocular sizes for stargazing.

(If you want a graduate-level education on binoculars, or if you want to dive deeper into some topics discussed here, please see the B&H Binocular Guide.)

Non e-commerce photographs © Todd Vorenkamp

The Binocular Advantage

When we think of magnified views of the stars or planets, many of us default to the telescope, and there is nothing wrong with that. I enjoy my terrestrial spotting scope for celestial viewing of some targets and I have shared my thoughts on the advantages of a spotting scope over a telescope for beginners.

But, when it comes to cost, simplicity, portability, and value, no optical device will top a good pair of binoculars for casual (and some in-depth) night sky observations.

Because most binoculars are lightweight and portable, you don’t need to spend time packing for a stroll to your backyard or a nearby park to look at the sky. Just grab them and go—or have a pair riding shotgun in your car—ready to be used during the day or night!

Additionally, there is a biological advantage to binocular (two-eye) viewing. Viewing the night sky with two eyes (even non-magnified) gives increased resolution, contrast, and color versus single-eye viewing. Binoculars enhance this advantage.

Almost any kind of binocular can be used to see the starry sky—but some offer advantages over others.

Almost any kind of binocular can be used to see the starry sky—but some offer advantages over others.

“Standard” Binoculars vs. “Astronomy” Binoculars

Very few binoculars these days are designed to be used primarily for astronomical use. In fact, almost all binoculars on today’s market can be used for a variety of purposes—birding, marine, travel, nature, landscape, etc.—so don’t get wrapped around the axle searching for pure astronomy optics.

Yes, some binoculars, like the discontinued Nikon ProStars, had specific astro-friendly coatings, but I found the ProStars perfect for daytime use on the bridges of large containerships and on my 24' sailboat. To emphasize this point, members of the Fujinon’s Polaris binocular family are known to be premium marine binoculars—all while equipped with north star astronomical branding.

Night Sky Targets

Stars: The #1 Night Sky Attraction for Binoculars

Numbers vary from source to source, but the unaided human eye can see approximately 5,000 stars from the surface of the Earth. At any given time, about half of those stars are blocked by the planet itself and many are dimmed by light pollution, depending on your location on the Earth—say, around 2,000 stars on any given night. But peer into the darkness through a decent pair of binoculars and suddenly you are seeing stars that you have never set eyes on before—according to some experts, 25 to 50x more stars than with the naked eye alone—that is 50,000-100,000 stars!

For those familiar with star magnitudes, the human eye can see, unaided, stars from 1 magnitude (brightest) to 6 magnitude (dimmest). With a classic 7x50 binocular (more on what the “7x50” numbers mean below) you can see 10 magnitude stars!

One of my favorite things to do with binoculars in the summer night sky is to point my pair at the Milky Way (our own galaxy’s gassy strip of stars) and get immersed in a stunning view of hundreds of stars (or more) in a single binocular view.

This is one of the best ways to employ an astronomical binocular—and, as a bonus, the most achievable astro viewing mission since “standard” binoculars can fit the bill.

Binocular magnification considerations: When looking at stars, because of their great distance, binocular magnification is not as much a factor, and a wider field of view might give you a better view. (See “Magnification” below.)

The Pleiades star cluster, or Subaru, taken through a Meade 70mm astrograph. 10x magnification.

The Pleiades star cluster, or Subaru, taken through a Meade 70mm astrograph. 10x magnification.

Moon

The moon is the first night sky binocular target of many stargazers. Why? Because it is big and bright and stunningly beautiful!

Contrary to popular belief, the full moon is not the best target for your binoculars (or camera) because the fully illuminated disc of the satellite will not show the awesome texture, relief, and features of a gibbous or crescent moon. Enjoy the full moon’s brightness for late-night drives or backyard fun, but break out your binoculars during the different phases of the moon to see the spectacular details of its mountains and craters—especially along the terminator (the line separating dark from light) on the lunar surface.

Binocular magnification considerations: More powerful binoculars will allow you to see lunar features with greater detail. (See “Magnification” below.)

The moon. Image taken through a Meade 70mm astrograph. Cropped from a 10x magnification image.

The moon. Image taken through a Meade 70mm astrograph. Cropped from a 10x magnification image.

“Shooting” Stars

Yes, you can use binoculars for enjoying meteor showers, but a bit of patience and luck is needed since any optic that magnifies an image also restricts your field of view. Grab a comfortable lawn or beach chair, a beverage, your binoculars, turn to face the radiant (the constellation from which most of the meteors are appearing) of your chosen meteor shower, and enjoy the show—reaching for the binos if you want to magnify a portion of the sky.

Binocular magnification considerations: For meteors, you will want a wide field of view through your binoculars because the radiant from which the meteors primarily originate during a shower can cover a fair amount of the sky. (See “Magnification” below.)

A meteor during the 2021 Perseid meteor shower. Images taken with a 14mm FUJIFILM lens. All binoculars will have a much narrower field of view, making seeing a shooting star through them more a matter of luck.
A meteor during the 2021 Perseid meteor shower. Images taken with a 14mm FUJIFILM lens. All binoculars will have a much narrower field of view, making seeing a shooting star through them more a matter of luck.

Solar Eclipse / Solar Observing

My very best views of the 2017 total solar eclipse were through a pair of binoculars. I was using a set of solar filters over the eyepieces until totality, and then, during totality, while firing my camera intermittently, I removed the filters and was treated, courtesy of my Nikon “birding” binoculars, to an unrivaled view of the total solar eclipse—of which my photos failed to convey the radiance and ethereal feel. You can also use a dedicated pair of solar binoculars for safe solar viewing.

WARNING: If using solar filters on standard binoculars, ensure they are made for viewing and in good working order. Using a dark neutral density filter for optical viewing will not protect your eyes from the powerful radiation of sunlight.

The August 2017 total solar eclipse. Image taken through a Nikon 300mm f/4 lens. 9x magnification.

The August 2017 total solar eclipse. Image taken through a Nikon 300mm f/4 lens. 9x magnification.

Binocular magnification considerations: Any binocular (ONLY with correct solar filters) may be used to view the sun and solar eclipses. Most dedicated solar binoculars have mid-range magnification. (See “Magnification” below.)

Dedicated solar binoculars are designed exclusively for viewing the sun safely.

Dedicated solar binoculars are designed exclusively for viewing the sun safely.
You can turn any pair of binoculars into solar viewing optics with a set of universal solar filters made from Mylar.

You can turn any pair of binoculars into solar viewing optics with a set of universal solar filters made from Mylar.

Planets

Yes, you can see the observable planets through binoculars, but their relative size and distance makes detailed viewing of these celestial bodies a bit of a challenge.

Binocular magnification considerations: With a good pair of binoculars of standard magnification, you can observe Jupiter and the four Galilean moons (Io, Calisto, Europa, and Ganymede) and the phases of Venus, but to see Saturn’s rings you’ll need high-powered binoculars. (See “Magnification” below.)

Jupiter and Saturn get close in December 2020. Image taken through a Leica APO-Televid 77 spotting scope at 30x magnification.

Jupiter and Saturn get close in December 2020. Image taken through a Leica APO-Televid 77 spotting scope at 30x magnification.

Comets

Comets are a great target for binoculars since the most spectacular rarely need the high magnification of a telescope to be enjoyed. In fact, astronomers using FUJIFILM/Fujinon’s large binoculars have been credited with the discovery of 15 new comets over the years!

Binocular magnification considerations: High magnification is not needed for some brighter comets but might be desired for distant comets with smaller tails. (See “Magnification” below.)

Comet NEOWISE. Image taken through a Meade 70mm astrograph. 10x magnification.

Comet NEOWISE. Image taken through a Meade 70mm astrograph. 10x magnification.

Deep Sky Objects

Yes, as with the planets, you may see some deep sky objects through binoculars like the Andromeda Galaxy (the most distant object you can see with the naked eye), star clusters, and nebulae (like the Orion nebula), but for serious observations of these beautiful night sky features, you’ll likely want to peer through a telescope instead.

It is also important to mention that, because we have all become accustomed to amazing astrophotography from ground and space-based telescopes over the years, your own eyes are not as sensitive to color at night as a camera. Therefore, brilliant gas clouds and nebulae will look much more monochromatic to the magnified eyeball through any optic.

Binocular magnification considerations: While some of the more prominent deep sky objects are available for viewing through standard power binoculars, more powerful pairs will allow for more detailed viewing. (See “Magnification” below.)

The Andromeda galaxy. Image taken through a Meade 70mm astrograph. 10x magnification.

The Andromeda galaxy. Image taken through a Meade 70mm astrograph. 10x magnification.

Ready for more? To read more about stargazing binoculars, click here. Part 2 discusses the features of binoculars and what makes certain binoculars better for stargazing. If you have questions about this first segment, please feel free to engage us in the Comments section, below.

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