This Week’s Sky at a Glance, September 16 – September 23

From late summer into autumn, the Greek tale of Perseus and Andromeda plays out on the eastern stage of the night sky each evening. Princess Andromeda, the daughter of Cepheus and Cassiopeia, is chained to the rocky coast of Ethiopia as a sacrifice to a vicious sea monster, portrayed by the constellation Cetus the Whale. Our hero Perseus, on his way home aboard Pegasus after beheading Medusa, rescues the princess and wins her unchained hand in matrimony.

The constellation Andromeda consists of two lines of stars stretching toward Perseus from a common point. That point is the bright star Alpheratz, which is officially Andromeda’s head but it also forms one corner of the Great Square of Pegasus. The bottom line of stars is more prominent, containing the orange star Mirach and ending with Almach, which resolves as a pretty double star in a small scope.

The highlight of the constellation is M31, the Andromeda Galaxy, the nearest spiral galaxy to our own Milky Way. A telescope is not required to see this. It looks great in binoculars, and in a rural area on a cloudless night you can see it with the naked eye as a smudge of light. Place Mirach at the bottom of your binocular view and perhaps raise it a bit to see a slightly dimmer star in the upper line of Andromeda. Continue up about the same distance to another star and find the fuzzy expanse of the Andromeda Galaxy nearby. A small telescope will show two other galaxies, M32 and M110, in the same field of view. M31 is 2.5 million light years distant and heading our way. We will have a spectacularly starry sky in a few billion years.

This Week in the Solar System

Saturday’s sunrise in Moncton is at 6:58 am and sunset will occur at 7:28 pm, giving 12 hours, 30 minutes of daylight (7:04 am and 7:32 pm in Saint John). Next Saturday the Sun will rise at 7:07 am and set at 7:14 pm, giving 12 hours, 7 minutes of daylight (7:12 am and 7:19 pm in Saint John). The Sun crosses the equator at 5:02 pm on Friday, September 22 to begin the autumn season in the northern hemisphere.

The Moon is new on Wednesday, making midweek a great time for seeking out those faint fuzzy objects with a telescope or binoculars. Jupiter sets around 8:30 this week, followed by Saturn a few hours later. It will be worthwhile to step outside around 6 am on Monday for a scenic view of Venus, Regulus, the crescent Moon, Mars and Mercury in a line about ten degrees long. Mercury appears very near to Mars this Saturday as it heads sunward, and Venus drops near Regulus on Wednesday.

The RASC NB star party at Fundy National Park takes place September 15 and 16 at the South Chignecto campground, and their telescopes will be set up on September 22 and 23 for the Fall Festival at Kouchibouguac National Park.

Questions? Contact Curt Nason at nasonc@nbnet.nb.ca.