Archive
07/12/2021 – Ephemeris – Two cultures look at the star pattern of Cygnus the swan
This is Ephemeris for Monday, July 12th. Today the Sun will be up for 15 hours and 18 minutes, setting at 9:27, and it will rise tomorrow at 6:09. The Moon, 3 days past new, will set at 11:33 this evening.
Last week I looked at the constellation of Cygnus the swan and the informal constellation or asterism made from most of its stars, the Northern Cross. Cygnus is the official International Astronomical Union constellation name. However, the indigenous Anishinaabe people of our area, and the northern Great Lakes, had another bird in mind when seeing these stars, which are now fairly high in the east in the evening: Ajijaak, (pronounced a-ji-jock) a Sand Hill crane. While the swan is flying, neck outstretched to the south through the Milky Way, the crane is flying northward with its long legs trailing behind. The bright star Deneb is at its head. I see more cranes than swans around here in recent years and hear their creaking-door-like calls, and can see a pair foraging, from time to time, in a field south of where I live.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hr). They may be different for your location.
Addendum
The IAU Cygnus the swan and the Anishinaabe Ajijaak the crane constellations demonstrated via an animated GIF image. Click on the image to enlarge it. Credit Stellarium (both star lore images are embedded in Stellarium). The Anishinaabe image is from Ojibwe Giizhig Anung Masinaaigan – Ojibwe Sky Star Map created by A. Lee, W. Wilson, and C. Gawboy.
07/08/2021 – Ephemeris – How to find the constellation of Cygnus the swan
This is Ephemeris for Thursday, July 8th. Today the Sun will be up for 15 hours and 23 minutes, setting at 9:29, and it will rise tomorrow at 6:06. The Moon, 1 day before new, will rise at 5:23 tomorrow morning.
Halfway up the sky in the east at 11 pm is the constellation of Cygnus the swan, flying south through the Milky Way. It is also called the Northern Cross. At the left, the tail of the swan or the head of the cross is the bright star Deneb, one of the stars of the Summer Triangle. The next star to the right is Sadr the intersection of the body and the wings of the swan seen in flight, or the intersection of the two pieces of the cross. There are two or three stars farther to the right that delineate the swan’s long neck or upright of the cross, that ends with the star Alberio, a beautiful double star in telescopes, in the beak of the swan or foot of the cross. The crosspiece of the cross extends to the stars on either side of the intersection star Sadr, while the swan’s wings extend for a couple more stars each side.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT-4). They may be different for your location.
Addendum
Animated Cygnus finder chart. Included also are, beside Deneb, the other stars of the Summer Triangle: Vega and Altair and their constellations Lyra the harp and Aquila. See if you can find them. Click on the image to enlarge it. Created using Stellarium.
06/29/2021 – Ephemeris – The Summer Triangle
This is Ephemeris for Tuesday, June 29th. Today the Sun will be up for 15 hours and 32 minutes, setting at 9:32, and it will rise tomorrow at 6:00. The Moon, 2 days before last quarter, will rise at 1:14 tomorrow morning.
Dominating the eastern sky at 11 pm are three bright stars. These are all first magnitude stars, members of the group of 21 brightest stars in the night sky. Highest, in the east, is Vega, the brightest of the three. It and a small, slim parallelogram of stars below it belong to the constellation of Lyra the harp. Below it to the northeast is Deneb, dimmest of the three at the head of the horizontally appearing Northern Cross, an informal constellation or asterism. Properly, Deneb is in the tail of Cygnus the swan flying south through the Milky Way. The third star of the three is Altair, lower still, but in the east-southeast at the head of Aquila the Eagle. These three stars are in a large asterism called the Summer Triangle, which will be with us through summer and fall.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT-4). They may be different for your location.
Addendum
The Summer Triangle finder animation showing first the unlabeled sky, Then the Summer Triangle with the stars labeled, then the constellations of those stars. Click on the image to enlarge it. Created using Stellarium and GIMP.
07/10/2020 – Ephemeris – The constellation Cygnus the swan
This is Bob Moler with Ephemeris for Friday, July 10th. Today the Sun will be up for 15 hours and 20 minutes, setting at 9:28, and it will rise tomorrow at 6:08. The Moon, 2 days before last quarter, will rise at 12:52 tomorrow morning.
Fairly high in the east at 11 p.m. Is the constellation of Cygnus the swan, flying south through the Milky Way. It is also called the Northern Cross. At the left, the tail of the swan or the head of the cross is the bright star Deneb, one of the stars of the Summer Triangle. The next star right is Sadr the intersection of the body and the wings of the swan seen in flight, or the intersection of the two pieces of the cross. There are two or three stars farther to the right that delineate the swan’s long neck or upright of the cross, that ends with the star Alberio in the beak of the swan or foot of the cross. The crosspiece of the cross extends to the stars on either side of the intersection star Sadr, while the swan’s wings extend to a couple more stars each.
The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Animated Cygnus finder chart. Included also are, beside Deneb, the other stars of the Summer Triangle: Vega and Altair and their constellations Lyra the harp and Aquila. See if you can find them. Click on the image to enlarge it. Created using Stellarium.
074/26/2016 – Ephemeris – The flying swan and Northern Cross
Ephemeris for Tuesday, July 26th. The Sun rises at 6:22. It’ll be up for 14 hours and 52 minutes, setting at 9:15. The Moon, at last quarter today, will rise at 1:09 tomorrow morning.
Fairly high in the east at 11 p.m. Is the constellation of Cygnus the swan, flying south through the Milky Way. It is also called the Northern Cross. At the left, the tail of the swan or the head of the cross is the bright star Deneb, one of the stars of the Summer Triangle. The next star right is Sadr the intersection of the body and the wings of the swan seen in flight, or the intersection of the two pieces of the cross. There are two or three stars farther to the right that delineate the swan’s long neck or upright of the cross, that ends with the star Alberio in the beak of the swan or foot of the cross. It takes a telescope, but Alberio splits into a beautiful blue and gold binary star.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Cygnus the Swan Created using Stellarium.
08/04/2015 – Ephemeris – Is it a swan or a cross?
Ephemeris for Tuesday, August 4th. The Sun rises at 6:32. It’ll be up for 14 hours and 32 minutes, setting at 9:04. The Moon, 2 days before last quarter, will rise at 11:33 this evening.
High in the east northeast as it gets dark flies the constellation of Cygnus the swan. This constellation is also known as the Northern Cross. The cross is seen lying on its side with the bright star Deneb at the head of the cross to the left. The rest of the cross is delineated in the stars to the right. As a swan, Deneb is the tail, the stars of the crosspiece of the cross are part of the leading edges of the wings as Cygnus flies south through the Milky Way. There are faint stars that also define the tips and trailing edges of its wings. It is a very good portrayal of a flying swan, like the mute swans we see on the wing in our area. This is the form the Greek god Zeus took to seduce the maiden Leda in the Leda and the swan affair, out of whose union Pollux was born, who was the twin of Castor, both of whom are also in the stars as the constellation Gemini. In Cygnus we are looking toward the direction that the Sun and the Earth are traveling as we orbit the center of the Milky Way.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Cygnus The Swan Created using Stellarium.
Note for telescope owners: The star that appears in the eye of the swan image above is Alberio (β Cygni), which splits into a beautiful binary star, whose component stars are blue and gold. It takes a bit more magnification than a pair of binoculars provides.
Note also the mythological citation in the program was omitted from the broadcast version due to time constraints.
07/17/2014 – Ephemeris – The constellation Cygnus the swan
Ephemeris for Thursday, July 17th. Today the sun will be up for 15 hours and 10 minutes, setting at 9:23. The moon, 1 day before last quarter, will rise at 12:25 tomorrow morning. Tomorrow the sun will rise at 6:14. | Fairly high in the east at 11 p.m. Is the constellation of Cygnus the swan, flying south through the Milky Way. It is also called the Northern Cross. At the left, the tail of the swan or the head of the cross is the bright star Deneb, one of the stars of the Summer Triangle. The next star right is Sadr the intersection of the body and the wings of the swan seen in flight, or the intersection of the two pieces of the cross. There are two or three stars farther to the right that delineate the swan’s long neck or upright of the cross, that ends with the star Alberio in the beak of the swan or foot of the cross. The crosspiece of the cross extends to the stars on either side of the intersection star Sadr, while the swan’s wings extend to a couple more stars each.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
CygnusTheSwan Created using Stellarium.
09/26/2013 – Ephemeris – The Milky Way is crossing overhead
Ephemeris for Thursday, September 26th. The sun will rise at 7:34. It’ll be up for 11 hours and 57 minutes, setting at 7:31. The moon, at last quarter today, will rise at 12:17 tomorrow morning. | At 10 this evening the Milky Way will pass directly overhead. The bright star Deneb of the Summer Triangle and at the head of the Northern Cross is directly overhead at that time. Deneb is incidentally the tail of Cygnus the swan. The Milky Way stretches from the northeast to the southwest where the Teapot of Sagittarius is tipping, pouring out its tea on the horizon. The Milky Way can be enjoyed with the naked eye, binoculars or telescope. With the naked eye, we see it as the pre-scientific cultures did. The Milky way was a pathway of milk, the path that the American Indian warriors journeyed to the hereafter, the stars their camp fires shining in the night. In reality it is what we can see of our galaxy.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Milky Way crosses the sky overhead at 10 p.m., September 26, 2013. Horizon to horizon view. Created using Stellarium.
09/02/2013 – Ephemeris – The Milky Way’s Great Rift
Ephemeris for Labor Day, Monday, September 2nd. The sun will rise at 7:06. It’ll be up for 13 hours and 10 minutes, setting at 8:16. The moon, 3 days before new, will rise at 5:19 tomorrow morning.
High overhead the Milky Way is seen passing through the Summer Triangle of three bright stars. Here we find the Milky Way split into two sections. The split starts in the constellation of Cygnus the Swan or Northern Cross very high in the east. The western branch of the Milky Way ends in the south. The dark dividing feature is called the Great Rift. Despite the lack of stars seen there, it doesn’t mean that there are fewer stars there than in the brighter patches of the Milky Way. The rift is a number of overlapping clouds of dust and gas about 300 light years away that obscure the light of the stars behind them. Sometimes binoculars can be used to find the edges of the clouds of the rift, as stars numbers drop off suddenly. This is especially easily seen in the constellation of Aquila.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Great Rift in the Milky Way. Created using Stellarium.
10/11/2012 – Ephemeris – North American Nebula
Ephemeris for Thursday, October 11th. The sun will rise at 7:53. It’ll be up for 11 hours and 10 minutes, setting at 7:04. The moon, 3 days past last quarter, will rise at 4:30 tomorrow morning.
Most of what we see in the Milky Way are just masses of stars, but there are bright clouds of gas , or to name them properly: emission nebulae. These bright clouds are areas of star formation. It is the ultraviolet light from young massive stars that light up the clouds they were formed from. A bright one, easily visible in binoculars is just about overhead at 9 p.m. Called the North American Nebula, a glow shaped much like our continent just east of the star Deneb, the northernmost star of the Summer Triangle, and brightest star in Cygnus the swan or Northern Cross. There are many other nebulae in the Milky Way, visible in binoculars and small telescopes. Many enjoyable hours can be spent sweeping the Milky Way for nebulae and star clusters.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
North American Nebula in Red. My old image.
The red object is the North American Nebula. Our eyes cannot perceive the color, due to hydrogen. This was a time exposure on film without telephoto. The bright star to the upper right is Deneb. The orientation is approximately correct if facing south. The photo also shows the stars that make up the glow of the Milky Way to the unaided eye.
Deneb Overhead at 9 p.m. on October 11. Created using Stellarium.
The North American Nebula is about the size and position of the C in Cygnus.
Better view of the North American Nebula taken by Scott Anttila.
This nebula is cataloged as NGC 7000.
Bob Moler's Ephemeris Blog 