This Week’s Sky at a Glance, 2019 October 26 – November 2 ~by Curt Nason
November is a time for mid-evening whale watching while the large constellation of Cetus the Whale is well placed for viewing in the southern sky. Many of its stars are not particularly bright so it can be elusive, but you can piece it together in a fairly dark sky. The eastern side of the square of Pegasus is a handy arrow that points down toward Diphda, the brightest star in Cetus. Also called Deneb Kaitos, “the tail of the whale,” it anchors a pentagram of stars forming the rear half of Cetus below dim Pisces. A circlet of stars to the upper left, west of Taurus, is the whale’s head.
A famous star in Cetus is Mira, perhaps the first star to be recognized as a variable or one that changes its brightness regularly. The name Mira translates as “wonderful.” It is a red giant star that expands and contracts; brightening as it expands. At minimum brightness it cannot be seen with binoculars, but every 11 months it brightens to easy naked eye visibility. The next maximum is expected to be reached in mid-November. Midway on the western side of the circlet of the whale’s head is a star which anchors an asterism that resembles a question mark. Don’t ask why, just try it. A scope or binoculars could reveal the galaxy M77 approximately midway between Mira and Menkar, the star at the bottom of the circlet. The planet Uranus, which is at opposition on Monday, can be seen within a binocular field above the double star to the upper right of the circlet.
In mythology Cetus represents the sea monster created by Poseidon to ravage the coastal area of Ethiopia as punishment for Queen Cassiopeia’s bragging. Her daughter Andromeda was chained to a rock at the seashore as a sacrifice to make the monster go away. Perseus was homeward bound on the back of Pegasus after slaying the Gorgon Medusa when he chanced upon Andromeda’s plight. He rescued the princess by using Medusa’s head to turn the monster to stone, winning the day and the hand of Andromeda.
This Week in the Solar System
Saturday’s sunrise in Moncton is at 7:51 am and sunset will occur at 6:14 pm, giving 10 hours, 23 minutes of daylight (7:54 am and 6:21 pm in Saint John). Next Saturday the Sun will rise at 8:00 am and set at 6:03 pm, giving 10 hours, 3 minutes of daylight (8:04 am and 6:10 pm in Saint John).
The Moon is new shortly after midnight on Monday morning, and it appears within a binocular view above Venus and Mercury in Tuesday evening twilight. For a real observing challenge, try to spot the extremely thin crescent Moon with binoculars in twilight Sunday morning when it is about 17 hours from new. Jupiter sets around 8:40 pm this week, an hour and a half after Venus and Mercury. Saturn remains well-placed for early evening observing above the handle of the Sagittarius Teapot asterism.
The Saint John Astronomy Club meets in the Rockwood Park Interpretation Centre at 7 pm on November 2. All are welcome.
Questions? Contact Curt Nason.