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Posts Tagged ‘Cygnus’

07/29/2022 – Ephemeris – The celestial Sand Hill Crane

July 29, 2022 Comments off

This is Ephemeris for Friday, July 29th. Today the Sun will be up for 14 hours and 46 minutes, setting at 9:12, and it will rise tomorrow at 6:26. The Moon, 1 day past new, will set at 10:14 this evening.

Let’s look again at the constellation called 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 and hear the cranes with their creaking-door-like calls, and see a pair 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 hours). They may be different for your location.

Addendum

Swan and the Crane constellations

The IAU Cygnus the swan and the Anishinaabe Ajijaak the Sand Hill crane constellations demonstrated via an animated GIF image. Credit 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.

07/18/2022 – Ephemeris – How to find the celestial eagle

July 18, 2022 Comments off

This is Bob Moler with Ephemeris for Monday, July 18th. Today the Sun will be up for 15 hours and 8 minutes, setting at 9:23, and it will rise tomorrow at 6:15. The Moon, 2 days before last quarter, will rise at 12:33 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 that dominate 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 toward the eagle.

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

Aquila finder animation

Animated Aquila finder chart, also showing Cygnus the swan. The named stars are the stars of the Summer Triangle. 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. The clouds of the Great Rift are easily visible. The red tinge of the image was due to the smoke haze from the wildfires in the western states. Taken by me and processed using Registax and GIMP.

07/15/2022 – Ephemeris – How to find the constellation of Cygnus the swan

July 15, 2022 Comments off

This is Ephemeris for Friday, July 15th. Today the Sun will be up for 15 hours and 14 minutes, setting at 9:25, and it will rise tomorrow at 6:12. The Moon, 2 days past full, will rise at 11:23 this evening.

Located 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 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

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. Created using Stellarium.

07/14/2022 – Ephemeris – The dimmest Summer Triangle star is actually the brightest

July 14, 2022 Comments off

This is Ephemeris for Thursday, July 14th. Today the Sun will be up for 15 hours and 15 minutes, setting at 9:26, and it will rise tomorrow at 6:11. The Moon, 1 day past full, will rise at 10:49 this evening.

This evening, when it gets dark enough, the bright star Deneb in Cygnus the swan will be high in the east-northeast. I’ll cover Cygnus tomorrow when the sky is darker. 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. That’s because of its vast distance of maybe 1,550 light years, 57 times the distance of Vega. If brought as close as Vega, Deneb would be as bright, at least, as the first quarter moon. It is possibly as bright as 196 thousand Suns; and it’s a huge star, possibly as large in diameter as the orbit of the Earth. For all this, it is only 23 or so times the mass of the Sun.

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

The Summer Triangle July 5, 2012 at 11 p.m. Created using Stellaruim and The Gimp.

The Summer Triangle. Created using Stellarium and The Gimp.

If you put Deneb in the search box, you will find that the content of the posts, over the years, about the star are nearly identical. However, the distance estimates vary widely. It is too far away for trigonometric parallax measurements by earth based telescopes. Though in the range of ESA’s Hipparcos and Gaia satellites, it is too bright. So other less accurate measurements are used. I don’t think it involves coin flipping. The assumed distance also affects estimates of luminosity, and mass.

06/27/2022 – Ephemeris – Finding the Summer Triangle

June 27, 2022 Comments off

This is Ephemeris for Monday, June 27th. Today the Sun will be up for 15 hours and 33 minutes, setting at 9:32, and it will rise tomorrow at 5:59. The Moon, 1 day before new, will rise at 5:13 tomorrow morning.

We’re nearly a week into summer, and the asterism or informal constellation called the Summer Triangle can be seen rising in the east as it gets dark. Highest of the three bright stars is Vega in the constellation Lyra the harp, whose body is seen in a narrow parallelogram nearby. The second star of the triangle is Deneb, in Cygnus the swan, lower and left of Vega, It appears dimmer than Vega because it is by far the most distant of the three. The third star of the Summer Triangle is seen farther below and a right of Vega. It is Altair in Aquila the eagle, and the closest. Altair is 16.5 light years away, Vega is 27 light years, while Deneb may be a whopping 2,600 light years away. One light year is 6 trillion miles (9 trillion kilometers).

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

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. Created using Stellarium and GIMP.

10/05/2021 – Ephemeris – Can you spot the North American Nebula?

October 5, 2021 Comments off

This is Bob Moler with Ephemeris for Tuesday, October 5th. Today the Sun will be up for 11 hours and 29 minutes, setting at 7:15, and it will rise tomorrow at 7:47. The Moon, 1 day before new, will rise at 7:46 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, that in photographs is shaped much like our continent, is just east of the star Deneb which is practically overhead in the evening. Deneb is 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.

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

North American Nebula finder animation

North American Nebula finder animation. I’ve dimmed down the stars a bit and increased the brightness of the Milky Way to aid in spotting the nebula. It requires dark skies to see it. I believe I can make it out with the naked eye too. Click on the image to enlarge it. Created using Stellarium and GIMP.

Deneb & North American Nebula

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

Better view of the North American Nebula taken by Scott Anttila.

Better view of the North American Nebula taken by Scott Anttila.

09/27/2021 – Ephemeris – The native peoples constellations of the Crane and the Moose

September 27, 2021 Comments off

This is Ephemeris for Monday, September 27th. Today the Sun will be up for 11 hours and 53 minutes, setting at 7:30, and it will rise tomorrow at 7:37. The Moon, 1 day before last quarter, will rise at 11:00 this evening.

The evening sky hosts two more of the constellations of the Anishinaabe native peoples of our area. Overhead, where the official constellation Cygnus the Swan is, or the Northern Cross is Ajijaak, the Sand Hill Crane flying northward through the Milky Way, wings outstretched, with its long legs trailing behind. In the eastern sky where the official constellation of Pegasus the flying horse is climbing the sky upside down is. His body is the Great Square, an informal constellation. To the Anishinaabe, it is the Mooz (Moose), who is upright. His magnificent antlers take up the dim official constellation of Lacerta the lizard between Pegasus and Cygnus. Also in the sky is Ojiig the Fisher, our Big Dipper, whose bloody tail will soon swoop down and paint the trees with their fall colors. (You can search for “Fisher” above right for his story, and his relevant appearances in autumn and late winter.)

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

Anishinaabe constallation of the Crane an Moose

The Anishinaabe constellations of Ajijaak, the Crane and Mooz (Moose) compared to the official International Astronomical Union (IAU) constellations. Created using Stellarium and GIMP.

The Ojibwe constellation art is part of the latest versions of Stellarium. Ojibwe (Anishinaabe) constellation art by Annette S Lee and William Wilson from Ojibwe Sky Star Map Constellation Guide, ISBN 978-0-615-98678-4.

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

July 26, 2021 Comments off

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.