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Posts Tagged ‘Altair’

07/17/2017 – Ephemeris – Constellations of the Summer Triangle III: Aquila the Eagle

July 17, 2017 Comments off

Ephemeris for Monday, July 17th. Today the Sun will be up for 15 hours and 9 minutes, setting at 9:23, and it will rise tomorrow at 6:14. The Moon, 1 day past last quarter, will rise at 2:08 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, the 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 times given are for the Traverse City/Interlochen area of Michigan. 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.

Aquila finder animation

Animated Cygnus finder chart. Created using Stellarium.

07/11/2017 – Ephemeris – Altair the nearest star of the Summer Triangle

July 11, 2017 1 comment

Ephemeris for Tuesday, July 11th. 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, 2 days past full, will rise at 10:59 this evening.

The southernmost star of the Summer Triangle is Altair, high in the east-southeast. The other two stars of the triangle are Vega nearly overhead in the east, and Deneb high in the east-northeast. Altair is the closest of the three at a distance of 16.7 light years away. One light year is nearly 6 trillion miles. Altair is 10 times the brightness of the Sun. If seen at Altair’s distance, the Sun would only be as bright as one of the two stars that flank it. What is rather different about Altair is its rapid rotation. While it’s almost twice the sun’s diameter, it rotates once in about 9 hours, The CHARA Interferometer at Mt. Wilson has actually imaged its squashed disk in the infrared. Our sun’s a slow poke, taking nearly a month to rotate once.

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

Addendum

Summer Triangle. Created using Stellarium.

Summer Triangle. Created using Stellarium.

Oblate Altair

False-color image of the rapidly rotating star Altair, made with the MIRC imager on the CHARA array on Mt. Wilson. Credit: Ming Zhao, University of Michigan

06/26/2017 – Ephemeris – Latest sunset and the apparent positions of the Summer Triangle stars

June 26, 2017 1 comment

Ephemeris for Monday, June 26th. Today the Sun will be up for 15 hours and 32 minutes, setting at 9:31, and it will rise tomorrow at 5:59. The Moon, 3 days past new, will set at 11:40 this evening.

Tonight we have the latest sunset of the year. From now on until December sunsets will become earlier. Other than the sunrise and sunset numbers, we’ll begin to notice it for real in a few weeks. At first that realization strikes me a sad note that summer is beginning to end. However the astronomer in me realizes that means more night-time hours, and that the summer Milky Way is coming. Of the three bright stars of the Summer Triangle overhead and in the east, two of its stars are in the milky band. They are Deneb to the north and Altair to the south. Vega, closest to the zenith is not in the band. Actually all the stars we see with the naked eye or small telescopes belong to the Milky Way galaxy.
The 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

Looking at the stars of the Summer Triangle and their location in and near the Milky Way band. Created using Stellarium.

06/22/2017 – Ephemeris – Now that it’s summer, lets check out the Summer Triangle

June 22, 2017 1 comment

Ephemeris for Thursday, June 22nd. Today the Sun will be up for 15 hours and 33 minutes, setting at 9:31, and it will rise tomorrow at 5:57. The Moon, 1 day before new, will rise at 5:45 tomorrow morning.

We’re a day 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 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 2600 light years away. One light year is 6 trillion miles (9 trillion km).

The times given are for the Traverse City/Interlochen area of Michigan. 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.

07/29/2016 – Ephemeris – Aquila the Eagle, third constellation of the Summer Triangle

July 29, 2016 Comments off

Ephemeris for Friday, July 29th.  The Sun rises at 6:26.  It’ll be up for 14 hours and 45 minutes, setting at 9:11.  The Moon, 3 days past last quarter, will rise at 3:20 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 seen now in the eastern sky in the evening.  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, which I talked about Tuesday, above and left of Aquila, flying in the opposite direction.

Times 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.

 

06/23/2016 – Ephemeris – Tis the season to view the Summer Triangle

June 23, 2016 Comments off

Ephemeris for Thursday, June 23rd.  Today the Sun will be up for 15 hours and 34 minutes, setting at 9:32, and it will rise tomorrow at 5:58.  The Moon, 3 days past full, will rise at 11:43 this evening.

Now that summer is here, the asterism or informal constellation called the Summer Triangle can be seen 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 lower and left of Vega, It appears dimmer than Vega because its is by far the most distant of the three.  The third star of the Summer Triangle is seen farther below and right of Vega.  It is Altair in Aquila the eagle, and the closest.  Altair is 16.7 light years away, Vega is 25 light years while Deneb may be a whopping 2600 light years away.   With a light year at 6 trillion miles.  That’s mind boggling to think in miles at least.

Times are for the Traverse City/Interlochen area of Michigan. 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.

11/20/2015 – Ephemeris – Finding the bright stars of November

November 20, 2015 Comments off

Ephemeris for Friday, November 20th.  The Sun will rise at 7:46.  It’ll be up for 9 hours and 24 minutes, setting at 5:10.   The Moon, 1 day past first quarter, will set at 2:17 tomorrow morning.

The Moon is beginning to brighten up the sky making constellation spotting somewhat difficult, so I thought we’d look for the brightest stars.  High in the west are the three stars of the Summer Triangle.  At the bottom in the southwest is Altair, the first of these to set.  A bit north of west the brightest, Vega.  Highest in the west is Deneb, which won’t officially set for those Interlochen northward.  Low in the south is the loneliest star Fomalhaut.  In the northeast is the winter star Capella, which also doesn’t set for the IPR listener area, but spends summer nights hiding behind hills and trees in the north.  Low in the east is the last of our bright stars, Aldebaran in Taurus the bull, which will be playing hide and seek with the Moon next week.

Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Autumn bright stars

The bright first magnitude stars of autumn shown for 8 p.m. November 20, 2015. If you are closer to your time meridian, we’re 43 minutes behind ours, you will see two more bright stars in the east: Red Betelgeuse and blue-white Rigel. Created using Stellarium.