Different times of year present opportunities to view different objects in the night sky. The fall/winter night sky offers a good opportunity to view open star clusters. Open star clusters are easy targets for beginners or casual viewers, since there are several that can be seen with the naked eye. Most can be seen with binoculars, and telescopes reveal these clusters’ fullest beauty. Let’s take a look at a few that are all in the same relative area in the sky…
Two easy targets to begin your open star cluster quest are the Pleiades and Hyades star clusters. These two are easily visible to the naked eye, and dont require super dark skies. The Hyades is a large “V” shaped cluster that forms the head of the constellation Taurus the bull. The Pleiades is quite a bit smaller, but still visible with the naked eye. Both of these clusters are near to Earth, aiding in their easy visibility. They appear low in the east in the fall after dark, but appear higher overhead in the winter months.
Our next stop is the Messier 44 cluster, also known as the Beehive cluster. This cluster is located in the very dim constellation Cancer the crab, so fairly dark skies are needed to find Cancer, and therefore M44. In ancient times, M44 was used to help forecast the weather. It is visible to the naked eye in very dark skies. If M44 couldn’t be seen, high, fair weather clouds were coming in, indicating an approaching weather front. Binoculars are recommended for this cluster, or a very wide field telescope lens. M44 is somewhat dense, featuring dozens of stars. Viewing this star cluster with binoculars inspired me to get a telescope because it’s amazing to see all of the stars so close. It’s definitely an out-of-this-world view!
Next up are the star clusters of the constellation Auriga the charioteer. Auriga is just to the north of Taurus, and contains the bright star Capella, making it easy to find. Auriga contains 3 open clusters in a row: M36, M37, and M38.
These clusters are also fairly dense and easy to see with binoculars. M37 is a bit dimmer, but more dense than the other two. Together, these 3 clusters in close proximity present a great opportunity to see open star clusters without having to scour the sky.
Another must-see for those hunting open star clusters is the Double Cluster of Perseus. Located between the top of Perseus (which is above Auriga) and below Cassiopeia, the “W” (which is above Perseus), this rare double star cluster can be seen with the naked eye as a small cloudy patch, though dark skies are needed. Binoculars or a wide field telescope lens will place both clusters in the same field of view. Several hundred stars are visible between the two clusters are visible. As a special bonus, the star-dense plane of the Milky Way are visible in the background. The Double Cluster of Perseus is one of my personal favorite open clusters to view. Definitely try and spot this one!
Last on our voyage is NGC-457, also known as the Owl Cluster. This cluster is located near the bottom left point of the “W” in Cassiopeia. While not a very dense cluster to see, it appears as a stick figure of a person, or as an owl with outstretched wings. It can be seen in binoculars, though a telescope is more helpful in seeing the owl figure shape. Check this one out!
The autumn sky presents a good opportunity to find open star clusters. Though they can be spotted in all parts of the sky year round, the fall sky gives several great opportunities to see open clusters within a smaller area of the sky, reducing the time spent searching and allowing more time for viewing. And, since these star clusters are fairly easy to find, they also make good targets for beginners, from naked eye viewing to binoculars and telescopes!
Don’t forget to share us with your stargazing friends on Facebook and Twitter!