Queen Cassiopeia in Greek mythology was beautiful and knew it. But her vanity turned out to be her downfall. She claimed that both she and her daughter, Andromeda, were even more beautiful than the sea nymphs. That claim did not sit well with Poseidon, the god of the sea, who promptly sent the sea monster Cetus to destroy their country.
Cassiopeia and her husband, Cepheus, then did what any loving parent in mythology might do – they chained Andromeda on the seashore to be eaten by the monster, hoping that would appease Poseidon. Fortunately, Perseus saved the day and rescued Andromeda so he could marry her, and they all got put in the sky for us to remember the story every time we see these constellations.
Cassiopeia is the W-shaped constellation (or M-shaped depending on the point of view) that is getting rather high in the northeastern sky in the evening. As long as the Big Dipper is very low on the northern horizon, Cassiopeia is the preferred way to find Polaris, the North Star. The points of the W open toward Polaris. The W is supposed to be the throne of Cassiopeia. Her beauty got her into the sky, and her vanity made it so she was forced to spend half of every night hanging upside down chained in her throne.
Cassiopeia is a great constellation to view through binoculars. It falls right along the center of the Milky Way and contains numerous open clusters, including the Messier objects M52 and M103. This rich star field also includes nebulosities (glowing gases) that show up usually only in long-exposure photographs. Some of these nebulae, such as the Bubble Nebula (NGC 7635) and the Pac-Man Nebula (NGC 281), have been named much more recently than Cassiopeia.
The other constellations in the story are all less obvious. Cepheus is a rather dim constellation a bit to the west of Cassiopeia. It looks like an upside down house to me. Andromeda, to the south, consists of two lines of stars branching from the Great Square of Pegasus. Perseus, an abstract “Y” of a constellation, follows Cassiopeia and Andromeda around the sky.
Between Perseus and Cassiopeia are NGC 869 and NGC 864, a pair of similarly sized open clusters. They are together called the Perseus Double Cluster and are among the most rewarding clusters to be seen in binoculars or small telescopes. They can be found just under a fist width to the left and slightly below the bottom-most star in the W of Cassiopeia. Many astronomers have wondered why this pair didn’t make Charles Messier’s famous list of deep sky objects.
This monthOn the morning of Nov. 13, Venus and Jupiter will be within a third of a degree of each other. This extraordinary conjunction is of the two brightest things in the sky besides the sun and the moon. Look for them to rise together in the east a little after 6 a.m. when it is starting to get light. On the days before and after the 13th, they will be steadily approaching toward, or retreating from each other, so not too far apart.
The comet I mentioned last month, Comet C-2017/O1 (ASASSN1), has been much dimmer than expected. If you want to see it now, you will need at least an 8- to 10-inch telescope and an up-to-date star chart.
The Leonid meteor shower peaks on the nights of Nov. 18 and Nov. 19. Associated with the orbit of comet Temple-Tuttle, every 33 years this shower could be quite spectacular, but this is not one of those years. You can expect to see 10 to 20 meteors per hour starting in the early morning after Leo rises.
Charles Hakes teaches in the physics and engineering department at Fort Lewis College and is the director of the Fort Lewis Observatory. Email him at [email protected]