At a distance of about 11 million light years, the Messier 81 (M81) galaxy group lies nearly overhead in the late northern spring and early summer and presents a handful of intriguing targets for backyard stargazers. This aggregation of gravitationally bound galaxies lies mostly in Ursa Major with some spillover into Camelopardalis. It’s one of the nearest galaxy groups to our own, and it contains some 40 galaxies and a total of about a trillion stars [Read more…] about Touring the M81 Galaxy Group
Share This:Deep Sky Observing
Articles about how to understand, find, and see celestial objects including stars, galaxies, nebulae, and star clusters with binoculars, telescopes, and the naked eye.
A Deep-Sky Tour of the ‘Hunting Dogs’
Just under the handle of the Big Dipper lies the dim constellation Canes Venatici, the Hunting Dogs, one of ten star groups devised by the 17th century astronomer Johannes Hevelius. Serving as the mayor of Danzig by day, Hevelius, understandably, preferred astronomy to politics and worked diligently to map the Moon, observe sunspots, and modernize maps of the northern night sky. In devising this constellation, he took into account past astronomical references to the two stars south of the Dipper’s handle as “hunting dogs” held on a leash by the huntsman represented by the constellation Bootes as they snapped at the hindquarters of the great bear of Ursa Major.
The brighter of the two stars in this dim constellation is 3rd-magnitude Alpha Canes Venaticorum, more informally called Cor Caroli, the ‘Heart of Charles’. The star was named after Charles I, the unfortunate monarch caught in the buzz saw of the English Civil War and beheaded in 1649. The fainter is 4th-magnitude Beta Canes Venaticorum, also known as Chara. As for the rest of the constellation, it isn’t much to look at. Like the adjacent Coma Berenices, few bright stars lie here because we’re looking in a direction out of the plane of the Milky Way and into intergalactic space. But there are plenty of galaxies here, and a couple of other deep-sky objects of note for backyard stargazers. Let’s take a short tour of a handful of highlights in this little constellation. [Read more…] about A Deep-Sky Tour of the ‘Hunting Dogs’
Share This:The Star Clusters of Cancer
Nearly overhead in the mid-evening hours of northern spring (and low over the northern horizon in the southern hemisphere), the constellation Cancer is the faintest of the twelve constellations of the zodiac. Many casual stargazers pass it by when looking from bright Gemini to the striking group Leo to the east. In city skies, the constellation is hard to see at all. Despite its inconspicuousness, there are some excellent sights in Cancer within reach of a telescope, including the superb star cluster M44, the Beehive Cluster, and the intriguing M67, one of the oldest known open star clusters. [Read more…] about The Star Clusters of Cancer
Share This:The Many Names of the Pleiades
The Pleiades star cluster in the constellation Taurus is one of a handful of objects in the heavens that never fail to amaze and inspire even the most experienced observers. As beautiful in an inexpensive pair of binoculars as in images from big professional telescopes, this star cluster presents visual observers an especially lovely sight with stars of an unearthly blue ensconced amid a faint frost of nebulosity. If there were more objects like it in the night sky, there would be a lot more amateur astronomers in the world [Read more…] about The Many Names of the Pleiades
Share This:Ambling Through Auriga
In this month’s sky tour, we grab our optics and tour of a few of the deep-sky highlights of the constellation Auriga, the Charioteer. Auriga lies along the relatively rich path of the northern Milky Way. And while it’s not Sagittarius, to be sure, the constellation has an eclectic selection of open clusters, nebulae, and interesting stars. Southern-hemisphere stargazers can also spot the constellation over the northern horizon in December through February [Read more…] about Ambling Through Auriga
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