Soaring high in the eastern sky and almost overhead at around midnight right now are the two stars marking the Hunting Dogs, known as Canes Venatici. In their vicinity, avid backyard astronomers can find a wealth of interesting objects to study, from a famous spiral galaxy to a cluster of distant star cities.

Located about a third of the way from the end of the Big Dipper's handle and below it, these dogs were placed in the sky to assist Boötes, the Bear Driver, in his daily task of pursuing the Big Bear (Ursa Major) around the pole of the heavens.

Unlike the two faithful canine companions of Orion, the Hunter (Canis Major and Canis Minor), which are separate constellations, the two Hunting Dogs of Boötes are both considered a single constellation (hence the plural "Canes" as opposed to the singular "Canis").

Cor Caroli marks the position of "Chara," one of the two hunting dogs in the mythological outline of the constellation. The other dog is named "Asterion" and is marked by the other, fainter star.

There are two objects in Canes Venatici worth looking for. The first is a beautiful and bright globular cluster, thought by many to be one of the most splendid in the sky. It was first seen by Charles Messier in 1764 and was listed as number three (M3) in his famous catalogue of deep-sky objects.

In a good pair of binoculars, M3 looks like a fuzzy 6th magnitude star. But with a small telescope it appears as a circular, nebulous object. Larger instruments will bring out the cluster's full glory: a beautiful ball of tiny countless star images, with streams of stars seeming to run out from all sides.

Roughly 40,000 light years away, the cluster's diameter is estimated to be 220 light years.

The other object, discovered by Messier in 1773, is M51. It is not a cluster of stars, but one of the nearest and brightest galaxies relative to our own. This was also the very first galaxy to show a spiral form and hence came to be known as the "Whirlpool Galaxy."

A good pair of binoculars will show it as a faint patch of light, whose total magnitude is about eight. Unfortunately, you will need a telescope of at least eight-inch aperture if you hope to get a glimpse of this galaxy's spiral arms.

Many years ago, under a very dark and clear sky near Southold, Long Island, I was able to able to discern the spiral coils of M51 using a 10.1-inch Dobsonian reflector. There is also a much smaller satellite galaxy, NGC 5195, that appears just off the end of one of the spiral arms of M51.

When you are gazing at this entire star system, keep in mind that you are looking out into space to a distance of some 35 million light-years. Amazing enough, but an even more amazing realm awaits your view off toward the south.

Astronomy popularizer Hans A. Rey called it the "Virgin's Diamond," though others refer to it simply as the "Great Diamond."

But also located within the Diamond is one of the most remarkable areas of the heavens. Sometimes called the Coma-Virgo Cloud of Galaxies, and often referred to in older astronomy texts as "The Field of the Nebulae," it is here that lies a veritable treasurer trove of numerous star cities. More than 3,000 galaxies have been photographed here with great observatory instruments.

If you own a good reflecting telescope of at least 6-inch aperture or greater, a sweep of this region will reveal literally dozens of these galaxies appearing as a myriad of faint and fuzzy patches of light. This is the only great cloud of galaxies that is available to the average (though somewhat experienced) amateur astronomer. Each and every one of these dim blobs is a star city, which likely contains tens of billions of stars!

And keep in mind that this cluster or cloud of galaxies is the nearest of the large aggregations of galaxies relative to our own. The best estimates indicate that it is located somewhere between 40 and 70 million light years from us.

So it is possible that as you run across these pale little patches of light in your telescope, irregularly shaped, round or elongated in appearance, that you are gazing upon galaxies whose light may have started toward the Earth around the time of the extinction of the dinosaurs.

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