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Posts Tagged ‘Northern Cross’

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.

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.

074/26/2016 – Ephemeris – The flying swan and Northern Cross

July 26, 2016 Comments off

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

CygnusTheSwan Created using Stellarium.

Cygnus the Swan Created using Stellarium.

08/04/2015 – Ephemeris – Is it a swan or a cross?

August 4, 2015 Comments off

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

CygnusTheSwan Created using Stellarium.

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

July 17, 2014 Comments off

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.

CygnusTheSwan Created using Stellarium.

09/26/2013 – Ephemeris – The Milky Way is crossing overhead

September 26, 2013 Comments off

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

Milky Way

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

September 2, 2013 Comments off

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.

The Great Rift in the Milky Way. Created using Stellarium.