The easier it is to find deep sky objects, the more fun you’ll have with amateur astronomy. You won’t need setting circles or computers. All you’ll need is your telescope, a finderscope, and a low power eyepiece. Add some star maps and you’re ready to go.

The art of starhopping requires you to locate a naked-eye star near your target deep sky object. Put the star in the center of your finderscope. Then use one of the techniques explained below to locate your object. Any fair finderscope will work; I prefer the Telrad reflex sight because of its versatility. It’s non-magnified but has three concentric illuminated rings: 4º, 2º, and ½º wide.

I will describe five starhopping techniques using different Messier objects as targets. You should use the lowest power eyepiece with the widest field of view that you have, to make it easier to locate objects. You can then switch to higher power as needed.

IN LINE WITH TWO STARS

The simplest technique is to "hop" from one star to another to your object. M31, the Andromeda Galaxy, can be quickly found using this technique. Aim your finder at the bright star Beta Andromedae. Then move your finder to another naked-eye star above it, Mu Andromedae. Continue to move your finder in the same direction, to a distance the same as the distance between the two bright stars. Now look in your eyepiece and you should see this great galaxy.

BETWEEN TWO STARS

The small globular cluster M80 in Scorpius can be elusive but you should have no difficulty if you use this technique. Locate the two brightest stars in Scorpius: Antares (Alpha) and Beta. Aim your finder exactly halfway down an imaginary line between the two. M80 should be right there.

Vary this technique. Look at star atlases to see which objects lie on a straight line between two bright stars. Aim your scope the appropriate distance between the two, whether that distance is ½ or ¹/3 or some other fraction that is easily approximated.

N A TRIANGLE WITH TWO STARS

While still in Scorpius you can learn another technique by locating the large globular cluster M4. It forms an isosceles triangle with Antares (Alpha) and Sigma.

Aim your finder 1º below the center of a line between Alpha and Sigma, the longest leg, and at a right angle to it. If you have a Telrad, aim it so that the 2º circle touches the halfway point between the two stars. M4 should be in your view.

You can find many other patterns of triangles among two naked-eye stars and a deep sky object. For example, the galaxy M94 is approximately 2º above and at right angle to the halfway point between the stars Cor Caroli (Alpha) and Beta, in Canes Venatici. Place the edge of the largest Telrad circle here.

AT THE INTERSECTION OF TWO LINES OF STARS

Some deep sky objects are not close enough to a naked-eye star to use any of these techniques. However, they usually fall along lines between several pairs of stars that are farther away. Aim your finder where these lines intersect to find your object.

For example, M3 is on an imaginary line between Arcturus and Cor Caroli. It is also on a line that connects Epsilon Bootis and Beta Comae (Berenices). Point your scope to where these lines intersect. With a low power eyepiece, you should be able to see the bright cluster almost in the center of your view.

IN THE EYEPIECE

To locate fainter objects, you will need to learn how to starhop through your eyepiece. Find a nearby bright star and aim your finder at it. Starting with your eye on the eyepiece with the bright star in the center, move the scope while following stars or star patterns to get to your target object.

To find the galaxy M108, aim your finder at Beta Ursa Majoris, the lowest star to the right in the bottom of the Dipper’s bowl. You will notice two fainter stars near Beta in the eyepiece. Starting with the one nearest Beta, move your scope to Beta; keep going in the same direction about ²/3 of a degree to a brighter star. Continue on this line, passing two more fainter stars which are an equal distance apart. Follow the last star to another star close to it at a 135º angle. On that line, the same distance away as these last two stars are from each other, is M108. Making a right angle to the south, you will find a bright star 1º away. Within the eyepiece will be M97, the Owl Nebula.

As you become more experienced, get out your star atlas and pick objects to find. Look at the brighter stars or star patterns nearby and determine which technique to use for each object. Then have fun finding them.

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