This Week’s Sky at a Glance, 2025 Sept 20 – Sept 27
This Week’s Sky at a Glance, 2025 Sept 20 – Sept 27
Small constellations tend to get overlooked unless, like Delphinus the Dolphin, they have fairly bright stars or an eye-catching pattern. Aries the Ram and cleverly named Triangulum aren’t quite as pretty as Delphinus but they do get noticed. Okay, Triangulum isn’t pretty but it is acute, situated below Andromeda in mid-evening. Below it is brighter Aries, which resembles a somewhat squashed triangle.
In mythology, the god Hermes sent a flying, golden ram to rescue a prince who was being sacrificed to end a famine. The prince showed his gratitude by slaughtering the ram and giving its fleece to a man in exchange for his daughter’s hand in marriage. The Golden Fleece later became the quest of Jason and the Argonauts. Over 2000 years ago the Sun was in Aries on the first day of spring, and the vernal equinox is still called the First Point of Aries despite having moved into the constellation Pisces long ago.
Triangulum is not associated with an exciting tale from mythology but at times it had been regarded as a tribute to both the Nile Delta and the island of Sicily. I use the tip of the triangle as a reference for locating the Triangulum Galaxy, also called M33. It is almost halfway and a tad to the right of a line from the tip to orange Mirach in Andromeda. Smaller and slightly more distant than the nearby Andromeda Galaxy (M31), this face-on spiral galaxy is dim but attainable with binoculars in a reasonably dark sky.
This Week in the Solar System
Saturday’s sunrise in Moncton is at 7:04 and sunset will occur at 7:20, giving 12 hours, 16 minutes of daylight (7:09 and 7:25 in Saint John). Next Saturday the Sun will rise at 7:12 and set at 7:06, giving 11 hours, 54 minutes of daylight (7:17 and 7:11 in Saint John). The Sun crosses the equator at 3:19 pm Tuesday to begin the autumn season.
The Moon is new this Sunday and to the lower left of Mars on Wednesday. Saturn is at opposition on Sunday, rising around sunset, and above it Neptune reaches opposition on Tuesday. By late in the week Jupiter will be rising around 1 am, followed by Venus four hours later. Mercury is too close to the Sun for evening observing.
Tune in to the Sunday Night Astronomy Show at 8 pm on the YouTube channel and Facebook page of Astronomy by the Bay.