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Posts Tagged ‘Cygnus’

07/26/2021 – Ephemeris – Albireo, a colorful double star in Cygnus the swan

July 26, 2021 Leave a comment

This is Ephemeris for Monday, July 26th. Today the Sun will be up for 14 hours and 52 minutes, setting at 9:15, and it will rise tomorrow at 6:23. The Moon, 3 days past full, will rise at 11:15 this evening.

Alberio is the name given to the star that is in the beak of the constellation of Cygnus the swan, which is high in the east these evenings. It is also at the foot of the asterism or informal constellation of the Northern Cross. To the naked eye Alberio looks like a single star, however even in small telescopes* its true nature is revealed. It is a double star whose individual star colors are strikingly different Its brightest star is yellow, and the dimmer star is blue. While star colors are subtle, these two, due to their apparent closeness, make an obvious color contrast. Unlike what your interior decorator says: In stars blue is hot, yellow, orange and red are cool. Also, it turns out that Alberio’s component stars don’t orbit each other. It is what is called an optical double. The blue star is a bit farther away than the yellow one, though they’re both around 430 light years away.

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.

* It will take at least about 20 power magnification to split. Binoculars won’t do it.

Addendum

Albireo finder animation

Animated Albireo finder chart. Albireo is located in the head of Cygnus the swan, or at the base of the Northern Cross. Tagged stars are, beside Albireo, the stars of the Summer Triangle: Deneb, Vega and Altair plus the star at the junction of the upright and crosspiece of the cross, Sadr. Created using Stellarium.

Albireo photographed in a telescope

Albireo, captured at high magnification by the staff of the Smithsonian Institution.

07/12/2021 – Ephemeris – Two cultures look at the star pattern of Cygnus the swan

July 12, 2021 Comments off

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

Swan and the Crane constellations

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

July 8, 2021 Comments off

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

Cygnus finder animation

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

June 29, 2021 Comments off

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

Summer Triangle finder animation

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.

08/17/2020 – Ephemeris – The Milky Way’s Great Rift.

August 17, 2020 Comments off

This is Ephemeris for Monday, August 17th. Today the Sun will be up for 13 hours and 56 minutes, setting at 8:44, and it will rise tomorrow at 6:49. The Moon, 1 day before new, will rise at 5:53 tomorrow morning.

High overhead the Milky Way is seen passing through the Summer Triangle of three bright stars. Here we find the Milky Way splits into two sections. The split starts in the constellation of Cygnus the Swan or Northern Cross very high in the east. The western part of the Milky Way ends southwest of Aquila the eagle. This 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 great dark cloud that obscures the light of the stars behind it. 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 Aquila.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Great Rift in the Summer Triangle

The Great Rift finder animation as seen in the Summer Triangle, also showing the constellations of Cygnus the swan and the the northern part of Aquila the Eagle. This image a stack of 5 30 second exposures taken the morning of the Perseid meteor shower in a vain attempt to capture some meteors.

Actual Aquila

Annotated and animated photograph taken of Aquila August 13, 2018 during the Perseid meteor shower, the same night the image above. Taken by me and processed using Registax and GIMP.

08/10/2020 – Ephemeris – The celestial eagle: Aquila

August 10, 2020 Comments off

This is Bob Moler with Ephemeris for Monday, August 10th. Today the Sun will be up for 14 hours and 15 minutes, setting at 8:55, and it will rise tomorrow at 6:41. The Moon, 1 day before last quarter, will rise at 12:20 tomorrow morning.

Aquila the eagle is a constellation that lies in the Milky Way. It’s in the southeastern sky as it gets dark. Its brightest star, Altair is one of the stars of the Summer Triangle, a group of three bright stars dominating the eastern sky in the evening now. Altair, in the head of the eagle, is flanked by two slightly dimmer stars, the shoulders of the eagle. The eagle is flying northeastward through the Milky Way. Its wings are seen in the wing tip stars. A curved group of stars to the lower right of Altair is its tail. Within Aquila the Milky Way shows many dark clouds as part of the Great Rift that splits it here. The other summer bird is Cygnus the swan above and left of Aquila, flying in the opposite direction.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Aquila

Aquila the Eagle in the southeastern sky. Created using Stellarium.

Actual Aquila

Annotated and animated photograph taken of Aquila August 13, 2018 during the Perseid meteor shower. Alas, no Perseids in this photograph. Taken by me and processed using Registax and GIMP.

The constellations Lyra, Cygnus and Aquila

Deneb with the other stars and constellations in the Summer Triangle. Created using Stellarium.

07/13/2020 – Ephemeris – The constellation of Ajijaak, the crane

July 13, 2020 1 comment

This is Bob Moler with Ephemeris for Monday, July 13th. Today the Sun will be up for 15 hours and 16 minutes, setting at 9:26, and it will rise tomorrow at 6:11. The Moon, 1 day past last quarter, will rise at 1:55 tomorrow morning.

Friday 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 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 his head. Where I live I see more cranes than swans these days and hear their creaking-door-like calls, and see a pair from time to time in a field south of where I live.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Swan and the Crane constellations

The IAU Cygnus the swan and the Anishinaabe Ajijaak the crane constellations demonstrated via an animated GIF image. Note the bright star of the Summer Triangle. Click on the Image to enlarge it. Created using Stellarium (both star lore images are embedded in Stellarium). The Anishinaabe image is from Ojibwe Giizhig Anung Masinaaigan – Ojibiwe Sky Star Map created by A. Lee, W. Wilson, and C. Gawboy.

 

07/10/2020 – Ephemeris – The constellation Cygnus the swan

July 10, 2020 Comments off

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

Cygnus finder animation

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.

07/02/2020 – Ephemeris – The star Deneb in Cygnus the swan

July 2, 2020 Comments off

This is Ephemeris for Thursday, July 2nd. Today the Sun will be up for 15 hours and 29 minutes, setting at 9:31, and it will rise tomorrow at 6:02. The Moon, 3 days before full, will set at 4:29 tomorrow morning.

This evening when it gets dark enough the bright star Deneb in Cygnus the swan will be high in the east-northeast. Deneb is the dimmest star of the summer triangle. Of the other stars of the triangle, Vega is higher in the east, while Altair is lower in the southeast. Deneb’s apparent magnitude, or brightness as seen from Earth, makes it the dimmest of the three bright stars. Its vast distance of possibly 2,600 light years is over 100 times the distance of Vega. If brought as close as Vega, Deneb would be as bright at least as the quarter moon. It is possibly as bright as 200 thousand Suns; and a huge star, possibly as large in diameter as the orbit of the Earth. For all this it is only 19 or so times the mass of the Sun.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

The constellations Lyra, Cygnus and Aquila

Deneb with the other stars and constellations in the Summer Triangle. Created using Stellarium.

Deneb & North American Nebula

One of my old photographs of Deneb and the North American Nebula digitized from a slide.

06/12/2020 – Ephemeris – The Summer Triangle proclaims that summer is almost here

June 12, 2020 1 comment

This is Bob Moler with Ephemeris for Friday, June 12th. Today the Sun will be up for 15 hours and 32 minutes, setting at 9:29, and it will rise tomorrow at 5:56. The Moon, 1 day before last quarter, will rise at 2:27 tomorrow morning.

Summer skies are coming. It’s only 8 days until summer officially arrives. It is a calendar day early this year because of the extra day added in February for the leap year. Looking to the eastern sky at 11 pm are three bright stars in a large triangle. The top star Vega is about half way up the sky to the zenith, and the brightest of the three. It’s in the small constellation of Lyra the harp. Lowest of the stars and just about due east is Altair in Aquila the eagle. Completing the triangle is Deneb in the northeast in the tail of Cygnus the swan or the head of the horizontal Northern Cross. These three stars make up the Summer Triangle. Be that as it may, the Summer Triangle will be in our evening sky moving slowly westward until December.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Finder animation for the Summer Triangle, seen in red for 11 pm, June 12th. Created using Stellarium and GIMP.