Astronomy Using Binoculars

Although they are not as appealing as a telescope, a good pair of binoculars are an excellent alternative, and will enable you to establish whether or not astronomy is for you without needing to go through the expense of buying a telescope. Binoculars are easy to use, they are light, and they are versatile.

As with telescopes, binoculars come in different sizes. As with telescopes, the bigger the aperture (the diameter of the objective lens), the more light can be captured and therefore the brighter objects will appear. But, again as with telescopes, the bigger binoculars are, the heavier and more difficult they are to handle.

10 x 50s are generally accepted as being an ideal size for day-to-day astronomy. 10 x 50 means that the binoculars have a magnification of 10x and an objective lens diameter of 50mm. A pair of 10 x 50s provide a field of view of about 6 degrees, which would allow you to see enough sky to span 12 moons (the moon covers about 0.5 degrees of the sky). A pair of 7 x 50s will provide a slightly larger field of view than a pair of 10 x 50s, but the magnification is not so good.

For larger binoculars it is advisable to use a tripod as this will prevent your arms from becoming tired, and will also avoid the image from jumping about. In fact, I have a pair of 8 x 30s, and it is pretty much impossible to hold them steady enough to be able to view an object such as a planet without the image bouncing around all over the place.

Binoculars provide a great addition to your astronomy tool kit, and are great when you want to quickly span the sky, darting from one object to another. I have three pairs (10 x 25s, 8 x 30s, and 10 x 50s), and I find a use for all three.