If you ask someone what device they need to observe the night sky, 9 out of 10 will answer “a telescope”. Although a telescope may seem the logical option, most optics experts may recommend at least one more item that would work better in some ways. Binoculars are much more versatile instruments that can reveal neighboring celestial bodies from Milky Way starfields to craters on the Moon.
In many aspects, binoculars are simply a better option than a telescope, especially for those starting out in astronomy. And observing with two eyes open rather than one seems more comfortable and natural for the majority of people. Binoculars also provide right-side-up images and have a wide field of view, making space objects easier to find. They require no special skills or expertise to set up — just make a step back, sling them around your neck and enjoy the night skies. That portability also makes them perfect for stargazing at specified locations which are unpolluted with light. You can find more than 100 certified International Dark Sky places – national parks, nature reserves – across the planet, many of them located in the US.
(In case you are feeling confused about a great variety of options available at the market, here’s the buying guide for binoculars for stargazing).
HOW TO CHOOSE ASTRONOMY BINOCULARS?
The first thing that makes regular binoculars referred to stargazing equipment is magnification.
What magnification is?
Magnifying power is defined as the ratio between the dimensions of the image and the object. For example, an optic device with magnifying power of 5 means that the object you are looking at will seem 5 times closer as if you would be looking at it with a naked eye.
For astronomical purposes, look for binoculars that magnify at least 7x. Since maximum magnification increases with binoculars weight. If the magnification exceeds 10 times, you likely won’t manage to hold the binoculars steady enough to get a sharp image. Huge binoculars, those with magnifications above 10x and aperture bigger than 50mm, can only be used with a tripod to get sharp images.
Binoculars with magnifying power lower than 7x are better to be used for bird watching, sightseeing or concerts.
Another key specification of any stargazing device is the exit pupil. This features describes the width of the beam of light as it leaves the eyepiece. By dividing the aperture by the magnification, you can calculate the exit pupil. So, for example, all 7×50 binoculars have an exit pupil of about 7mm and 10x50s have exit pupils of 5mm.
Field of View
Another feature to consider is field of view (or angular area, an astronomy term for field of view, may be used in some manuals for binoculars). Usually stamped on some part of the binoculars, angular area is measured either as a certain number of feet at 1,000 yards or in degrees.
To convert feet at 1,000 yards into degrees, divide the number of feet by 52.5 (e.g. 325/52.5 = 6.2°). Higher field of view provides extended view to identify distant objects. However, bigger magnification is a result of reduced field of view.
Most binoculars have a field of view around 6° or 7°. Some high-power models will shrink this to 3° to 5°, while wide-angle models will take in 8° to 10°.
TOP TIPS FOR BINOCULAR STARGAZING
- Choose the Date
Generally, the best time for discovering the galaxy is when the moon is in a crescent or gibbous phase, or other words when it’s not present in the sky at all. Literally, when the moon is full, there’s so much light in the skies that it washes out everything else.
- Find a Proper Dark Site
A whole potential of stargazing can be experienced in the least light polluted places. Luckily, the great amount of uninhabited national parks and deserts allows people to go stargazing. If there are no resources to plan a trip, try to move somewhere in the outdoors. Remember, the further you are from the city, the better chance to enjoy the night skies you will have.
- Find the Moon First
The basic tip for beginners. Use Moon as the point of reference for all that celestial bodies you are going to observe in the dark skies
- Find the Planets
Jupiter and Saturn are two most easily sighted through binoculars planets. Each should be can be seen under right conditions.
- Use stargazing Apps
If it’s your first time, try sky-charting apps that will help to find most celestial bodies. Most popular are Sky Safari 5, Jupiter Guide, Gas Giants and Sky and Telescope.
- Find the Milky Way
Unfortunately, this astronomical sight cannot be observed anywhere. Best places to see The Milky Way are Glacier National Park, Montana, Afton Canyon, California and Black Canyon of the Gunnison National Park in Colorado Rockies.
- Find the Constellations
Contemporary astronomy recognizes 88 different constellations. They are dedicated to 42 animals, 29 inanimate objects and 17 humans or mythological characters mostly of Greek origin.
- Look further
With more powerful binoculars, it is possible to observe galaxies even beyond our own Milky Way, such as the Andromeda Galaxy and its satellite galaxies M32 and M110.
- Look for the International Space Station
It’s not a mysterious dark sky object, but some users claimed it’s really fun to watch NASA Space Station moving around the Earth. FYI, they have a website dedicated to tracking ISS.
The Bottom Line:
You don’t need to buy a $1,000 telescope with a tripod and carry it to the mountains on your back. You need to decide how much money you are ready to invest in your stargazing gear. Browse the web, compare product features, and make a purchase.