This Week’s Sky at a Glance, May 27 – June 3 ~by Curt Nason
Warmer days and extended twilights are indications that the summer solstice is only a few weeks away. Also, the celestial advent of the season, the Summer Triangle asterism, is completely above the horizon in twilight. Halfway up in the eastern sky is blue-white Vega; lucida of the constellation Lyra the Lyre and the fifth brightest star of the night sky. Just above the eastern horizon is Altair, the central star of a linear trio that marks the head of Aquila the Eagle. The isosceles triangle is completed in the northeast by Deneb in the tail of Cygnus the Swan.
Just as the Big Dipper is an asterism in Ursa Major, Cygnus contains a well-known asterism called the Northern Cross. The long neck of the swan, or the base of the cross, terminates almost between Vega and Altair at the star Albireo. A small scope or binoculars will reveal Albireo as a pair of yellow and blue stars (or gold and sapphire if you have expensive equipment). A short distance from Altair toward Vega is the tiny constellation Sagitta the Arrow, and beyond Sagitta is elusive Vulpecula the Fox.
Look to the upper right of Sagitta’s feathered end with binoculars for the upside-down asterism of the Coathanger. Just below the arrow shaft is the distant star cluster M71, appearing as a tiny blur. Another blur can be seen in a binocular field above the arrowhead: M27, the Dumbbell Nebula, which is the remnant of a Sun-like star after it ran out of fuel and blew off its outer layers of gas. Next, point your binos behind the western (upper) wing of the swan. Can you find the large Happy Face asterism?
This Week in the Solar System
Saturday’s sunrise in Moncton is at 5:34 am and sunset will occur at 8:58 pm, giving 15 hours, 24 minutes of daylight (5:42 am and 9:00 pm in Saint John). Next Saturday the Sun will rise at 5:30 am and set at 9:04 pm, giving 15 hours, 24 minutes of daylight (5:38 am and 9:06 pm in Saint John).
The Moon is at first quarter on Thursday, providing great views in a scope all week to share with your friends. Jupiter is highest in the sky and at its best soon after twilight, while Mars is dimming and sets at 10:30 pm. The shadows of Jupiter’s moons Io and Ganymede might be seen on the planet’s cloud tops through a telescope at high magnification this Saturday between 9:16 and 9:40 pm, and again the following Saturday between 11:11 and 11:21 pm. Saturn rises around 11 pm and is still well-placed for observing by morning twilight. Venus dominates the morning sky, rising nearly two hours before sunrise.
There will be free public observing at the Moncton High School Observatory after sunset on Friday, May 26. Those attending the Nature NB Festival of Nature at Kouchibouguac National Park on June 2 – 4 should also check out the RASC NB star party at the park for solar observing, talks and evening observing. See the park website for a schedule. The Saint John Astronomy Club meets at the Rockwood Park Interpretation Centre on June 3 at 7 pm. All are welcome.
Questions? Contact Curt Nason.