This Week’s Sky at a Glance, 2019 November 16 – 23 ~by Curt Nason
Open clusters, sometimes called galactic clusters, are groups of relatively young stars (usually less than 500 million years old) that formed from the same vast cloud of gas and dust. The Pleiades cluster (M45) in the shoulder of Taurus the Bull is seen easily with the naked eye because it is fairly close at 440 light years (mind you, a light year is 9.5 trillion kilometres). The V-shaped Hyades in the face of Taurus is the closest at 150 light years, although Aldebaran at one end of the V is actually a foreground star at a distance of 65 light years. Many other clusters are greater than ten times farther and require binoculars or a telescope to be seen at all, usually as a hazy patch with some individual stars.
To the left of Taurus is a pentagram of stars marking the head, shoulders and knees of the constellation Auriga the Charioteer. One of those stars – in Auriga’s right knee, with him facing us – is officially part of Taurus. Point your binoculars halfway between this star and the one in Auriga’s right shoulder. Open cluster M36 is just inside the line between the stars, and M37 is just outside. They look like fuzzy patches because, at distances of greater than 4000 light years, a telescope is required to resolve individual stars. Further inside is the diffuse open cluster M38, midway between the right shoulder and left knee. All three clusters can be seen together in wide-field binoculars
This Week in the Solar System
Saturday’s sunrise in Moncton is at 7:20 am and sunset will occur at 4:46 pm, giving 9 hours, 26 minutes of daylight (7:23 am and 4:53 pm in Saint John). Next Saturday the Sun will rise at 7:30 am and set at 4:40 pm, giving 9 hours, 10 minutes of daylight (7:32 am and 4:47 pm in Saint John).
The Moon is near the Beehive star cluster in the constellation Cancer before sunrise on Monday, and it is at third quarter on Tuesday. Mercury has jumped into the morning sky, rising more than an hour before sunrise this weekend, and over the week it will close the gap to Mars from 15 degrees to 10 degrees (a fist-width at arm’s length). Venus lies 7 degrees to the lower right of Jupiter in the evening sky this Saturday, and by next Saturday it will be less than 2 degrees below Jupiter. By December 9, Venus will be 3 degrees below Saturn. The Leonid meteor shower peaks on Monday morning, but we will have to wait for the return of Comet Tempel-Tuttle in about 14 years before this shower produces a significant number of shooting stars. For a brief time in 1966, some people were seeing 40-50 meteors per second at the peak of the shower; more like a torrent. Meteor experts are predicting a possible, but brief (maybe half an hour), outburst from the Alpha Monocerotid shower after midnight Thursday evening (centered on 12:50 am Friday morning). They will be emanating from near the bright star Procyon to the left of Orion.
The provincial astronomy club, RASC NB, meets in the UNB Fredericton Forestry-Earth Sciences building at 1 pm this Saturday. All are welcome.
Questions? Contact Curt Nason.