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Ephemeris: 09/23/2024 – Scanning the Milky Way with binoculars
This is Ephemeris for Monday, September 23rd. Today the Sun will be up for 12 hours and 5 minutes, setting at 7:37, and it will rise tomorrow at 7:33. The Moon, 1 day before last quarter, will rise at 10:50 this evening.
Now that the Moon has fled the early evening skies the Milky Way is showing up again, if you’re at a dark site. I’ve always said that August and September are the best times to view what I call the summer Milky Way, even now that it’s not technically summer anymore. The Teapot asterism in the constellation of Sagittarius is low in the south-southeast, pouring its tea on the horizon. It is in that direction we are looking towards the center of our Milky Way Galaxy. The Summer Triangle is high in the South with Vega and Deneb, two of its stars near the zenith. All the Milky Way is an invitation to scan it with the pair of binoculars or a very low power telescope. One doesn’t need a chart. Just wander through the Milky Way to find many star clusters, groups of stars and nebulae.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum (Some binocular wonders)
The Coathanger
The North American Nebula
08/19/2022 – Ephemeris – Finding the small constellations near the Summer Triangle
This is Ephemeris for Friday, August 19th. Today the Sun will be up for 13 hours and 52 minutes, setting at 8:41, and it will rise tomorrow at 6:51. The Moon, at last quarter today, will rise at 12:32 tomorrow morning.
I’ve already talked about the three constellations whose bright stars mark the Summer Triangle: Vega in Lyra the harp, Deneb in Cygnus the swan, and Altair in Aquila the eagle. There are two small constellations near the south end of the triangle near Altair. These are Delphinus the dolphin and Sagitta the arrow. Delphinus is easily spotted, as it’s five or six stars appear as a tiny dolphin leaping out of the water. Sagitta appears as a very short arrow. An interesting sight can be spotted in binoculars near the tail end of Sagitta. It’s 7 stars in a nearly straight line, with a hook of four stars below the center of the line. It’s called The Coathanger. It’s even better if seen in a finder telescope, which inverts the image.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.
Addendum
Finding the small constellations of Delphinus the dolphin and Sagitta the arrow among the stars and constellations of the Summer Triangle. Created using Stellarium and GIMP.
How to locate the binocular asterism of the Coathanger. It is also known as Collinder 399, Brocchi’s Cluster and Al Sufi’s Cluster. It’s not a real star cluster, but a random arrangement of stars at various distances, that from the solar system make a distinctive pattern.
08/23/2019 – Ephemeris – Two small constellations around the Summer Triangle
Ephemeris for Friday, August 23rd. Today the Sun will be up for 13 hours and 41 minutes, setting at 8:35, and it will rise tomorrow at 6:55. The Moon, at last quarter today, will rise at 12:43 tomorrow morning.
Located below the eastern edge of the Summer Triangle of three of the brightest stars in the sky, which is overhead in our sky at 10 p.m., is the tiny constellation of Delphinus the dolphin. Delphinus’ 6 stars in a small parallelogram with a tail, really does look like a dolphin leaping out of the water. The parallelogram itself has the name Job’s Coffin. The origin of this asterism or informal constellation is unknown. Of the dolphin itself: the ancient Greeks appreciated this aquatic mammal as we do, and told stories of dolphins rescuing shipwrecked sailors. There’s another tiny constellation to the right of Delphinus, Sagitta the arrow a small thin group of 5 stars, which represents Cupid’s dart. Above-right of Sagitta binoculars will find a little star group called the Coat hanger.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Delphinus and Sagitta finder animation. Created using Stellarium and GIMP.
Closeup of Sagitta and the binocular asterism the Coathanger. Created using Stellarium.
09/10/2018 -Ephemeris – The Coathanger in the sky
Ephemeris for Monday, September 10th. The Sun will rise at 7:15. It’ll be up for 12 hours and 47 minutes, setting at 8:02. The Moon, 1 day past new, will set at 8:57 this evening.
Just about every amateur astronomer knows a little asterism or informal constellation called the Coathanger. It’s stars are mostly below naked eye visibility, but it is a great sight in binoculars. It’s located along a line from Altair in Aquila the eagle to Vega in Lyra the harp. These are two star of the Summer Triangle. It is also just west of, or right of, the constellation Sagitta the arrow. It consists of six stars in just about a perfectly straight line with four stars in a tight group south of them making the hook. In telescope finders which invert the image the Coathanger appears right-side-up. Arab astronomer Al Sufi discovered it and described it in 964 AD. It has the catalog designation of Collinder 399. It is also known as Brocchi’s Cluster.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
How to find the Coathanger. Look for the Summer Triangle. On the line from Altair to Vega the Coathanger can be found. Star imaged by Bob Moler.
Binocular view of the Coathanger. From the original resolution of the above photograph.
Telescope finder view of the Coathanger. Telescope finders usually invert the image, so it looks like a proper coat hanger.
09/07/2015 – Ephemeris – Small summer constellations
Ephemeris for Labor Day*, Monday, September 7th. The Sun will rise at 7:11. It’ll be up for 12 hours and 56 minutes, setting at 8:08. The Moon, 2 days past last quarter, will rise at 2:47 tomorrow morning.
Located below the eastern edge of the Summer Triangle of three of the brightest stars in the sky, which is overhead in our sky at 10 p.m., is the tiny constellation of Delphinus the dolphin. Delphinus’ 6 stars in a small parallelogram with a tail, really does look like a dolphin leaping out of the water. The parallelogram itself has the name Job’s Coffin. The origin of this asterism or informal constellation is unknown. Of the dolphin itself: the ancient Greeks told stories of dolphins rescuing shipwrecked sailors. There’s another tiny constellation to the right of Delphinus, Sagitta the arrow a small thin group of 5 stars, which represents Cupid’s dart. Behind Sagitta binoculars will find a little star group called the Coat hanger.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Summer Triangle. Created using Stellarium and The Gimp.
Delphinus, Sagitta and the Coat hanger. Diagram created using Stellarium.
* In the US Labor Day is celebrated on the first Monday in September and is considered the unofficial end of summer. The weather generally agrees. Last week we had a preview of fall weather. This week, except for today has been hot. The outlook for next week is looking decidedly cooler. Most schools in Michigan start the day after Labor Day. and end after June 1st. The unofficial start of summer is Memorial day, the last Monday in May.
08/20/2012 – Ephemeris – Celestial Dolphin and Cupid’s dart
Ephemeris for Monday, August 20th. The sun rises at 6:51. It’ll be up for 13 hours and 47 minutes, setting at 8:39. The moon, 3 days past new, will set at 9:48 this evening.
Located below the eastern edge of the Summer Triangle of three of the brightest stars in the sky, which is nearly overhead sky at 10 p.m., is the tiny constellation of Delphinus the dolphin, which is seen high in the south. Delphinus’ 6 stars in a small parallelogram with a tail, really does look like a dolphin leaping out of the water. The parallelogram itself has the name Job’s Coffin. The origin of this asterism or informal constellation is unknown. Of the dolphin itself: the ancient Greeks appreciated this aquatic mammal as we do, and told stories of dolphins rescuing shipwrecked sailors. There’s another tiny constellation to the right of Delphinus, Sagitta the arrow, which represents Cupid’s dart. [Off the tail of Sagitta binoculars will find a cute inverted coat hanger in the stars.]
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location. Bracketed text was removed from the audio program due to time constraints.
Addendum
Delphinus, Sagitta and the Coat hanger. Diagram created using Stellarium.
Bob Moler's Ephemeris Blog 