APOD: The W in Cassiopeia (2016 Mar 18)

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APOD: The W in Cassiopeia (2016 Mar 18)

Post by APOD Robot » Fri Mar 18, 2016 4:15 am

Image The W in Cassiopeia

Explanation: A familiar, zigzag, W pattern in northern constellation Cassiopeia is traced by five bright stars in this colorful and broad mosaic. Stretching about 15 degrees across rich starfields, the celestial scene includes dark clouds, bright nebulae, and star clusters along the Milky Way. In yellow-orange hues Cassiopeia's alpha star Shedar is a standout though. The yellowish giant star is cooler than the Sun, over 40 times the solar diameter, and so luminous it shines brightly in Earth's night from 230 light-years away. A massive, rapidly rotating star at the center of the W, bright Gamma Cas is about 550 light-years distant. Bluish Gamma Cas is much hotter than the Sun. Its intense, invisible ultraviolet radiation ionizes hydrogen atoms in nearby interstellar clouds to produce visible red H-alpha emission as the atoms recombine with electrons. Of course, night skygazers in the Alpha Centauri star system would also see the recognizable outline traced by Cassiopeia's bright stars. But from their perspective a mere 4.3 light-years away they would see our Sun as a sixth bright star in Cassiopeia, extending the zigzag pattern just beyond the left edge of this frame.

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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by Boomer12k » Fri Mar 18, 2016 4:53 am

My middle initial, and that is how I always remember it.

Lots of things there, and very interesting.

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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by Ann » Fri Mar 18, 2016 5:11 am

Ah, the W, the Queen, or the McDonalds in the sky! It's a beautiful sight, and Rogelio Bernal Andreo's widefield image is superb. So many things are going on there - look at the large semicircle of glowing red gas surrounding mighty Gamma Cassiopeia, the thick dark dust lane seemingly hanging down from it, and the bluish mountain tops of IC 59 and IC 63 forming one end of the arc of emission. And there are so many other things here, of course, like the lovely Owl Cluster, also known as the E.T. Cluster or NGC 457. And there is of course the striking Pacman Nebula.

I don't have my software here, but there is a soft reddened patch to the left of Caph. Can anyone tell me what it is?

Ann
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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by the spelling bee » Fri Mar 18, 2016 5:32 am

It is an 'M', really.

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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by alter-ego » Fri Mar 18, 2016 5:46 am

Ann wrote:I don't have my software here, but there is a soft reddened patch to the left of Caph. Can anyone tell me what it is?
I can't find a name for that soft patch specifically, but both IC63/59 appear to be part a larger nebula complex surrounding Gamma Cas. The "Gamma Cas Nebula" may be this larger group (also referred to as Sh2-185?)

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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by Harry D1 » Fri Mar 18, 2016 1:37 pm

But from their perspective a mere 4.3 light-years away they would see our Sun as a sixth bright star in Cassiopeia, extending the zigzag pattern just beyond the left edge of this frame.
I really like these 3D perspectives. It is always interesting to me where we are relative to other star systems. Sometimes it's a little difficult to get that perspective from 3D star maps and Astronomy software.
Very nicely done.

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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by neufer » Fri Mar 18, 2016 1:52 pm

http://www.online-literature.com/james_joyce/ulysses/9/ wrote: . Ulysses Episode 9
. Scylla And Charybdis


STEPHEN (Stringendo.) He has hidden his own name, a fair name, William, in the plays, a super here, a clown there, as a painter of old Italy set his face in a dark corner of his canvas. He has revealed it in the sonnets where there is Will in overplus. Like John O'Gaunt his name is dear to him, as dear as the coat of arms he toadied for, on a bend sable a spear or steeled argent, honorificabilitudinitatibus, dearer than his glory of greatest shakescene in the country. What's in a name? That is what we ask ourselves in childhood when we write the name that we are told is ours. A star, a daystar, a firedrake rose at his birth. It shone by day in the heavens alone, brighter than Venus in the night, and by night it shone over delta in Cassiopeia, the recumbent constellation which is the signature of his initial among the stars. His eyes watched it, lowlying on the horizon, eastward of the bear, as he walked by the slumberous summer fields at midnight, returning from Shottery and from her arms.
Art Neuendorffer

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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by Visual_Astronomer » Fri Mar 18, 2016 3:50 pm

A beautiful region of the sky, stunning in binoculars, which reveal numerous clusters and a rich tapestry of stars. I haven't tried to find the glow around Gamma Cass, but the PacMan nebula certainly lives up to its moniker. An excellent image!

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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by starsurfer » Fri Mar 18, 2016 6:02 pm

Ann wrote:I don't have my software here, but there is a soft reddened patch to the left of Caph. Can anyone tell me what it is?

Ann
This is the irregular dwarf galaxy IC 10, a nice closeup by NOAO. Other objects of interest in this image include the red planetary nebula Sh2-188 to the left of NGC 457. Ken Crawford has an excellent closeup image.
Above Ruchbah is the starforming region Sh2-187, an image by Tero Turunen.
The clusters between Ruchbah and Segin include NGC 663 and NGC 654 as well as a few others. Thomas Davis has a nice overview of this area.
The small blue reflection to the south of Caph is vdB1, a rare closer view by Adam Block.

Finally I propose a treasure hunt, somewhere in the image is the Sailboat Cluster (NGC 225). Can you find it? To give you a clue, a nice image by Antonio Sánchez.

An interesting note, this particular mosaic was actually released quite a few years ago.

Cassiopeia is one of my favourite constellations and I always see it's W instantly in the autumn and winter night sky. It also has a fantastic menagerie of deep sky objects for telescopic exploration by visual observers and astrophotographers.

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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by Ann » Fri Mar 18, 2016 6:28 pm

starsurfer wrote:
Ann wrote:I don't have my software here, but there is a soft reddened patch to the left of Caph. Can anyone tell me what it is?

Ann
This is the irregular dwarf galaxy IC 10, a nice closeup by NOAO. Other objects of interest in this image include the red planetary nebula Sh2-188 to the left of NGC 457. Ken Crawford has an excellent closeup image.
Above Ruchbah is the starforming region Sh2-187, an image by Tero Turunen.
The clusters between Ruchbah and Segin include NGC 663 and NGC 654 as well as a few others. Thomas Davis has a nice overview of this area.
The small blue reflection to the south of Caph is vdB1, a rare closer view by Adam Block.

Finally I propose a treasure hunt, somewhere in the image is the Sailboat Cluster (NGC 225). Can you find it? To give you a clue, a nice image by Antonio Sánchez.

An interesting note, this particular mosaic was actually released quite a few years ago.

Cassiopeia is one of my favourite constellations and I always see it's W instantly in the autumn and winter night sky. It also has a fantastic menagerie of deep sky objects for telescopic exploration by visual observers and astrophotographers.
Thanks, starsurfer! :D I thought that might be IC 10, but I wasn't sure.

Thanks for your great links. NGC 663 looks quite impressive in Thomas Davis's image, and that amazing little convoluted knot of gas and dust in Adam Block's image is just wonderful.

I couldn't find the Sailboat Cluster, so I cheated and asked my software to find NGC 225. Indeed, it does look quite sailboat-y!

Can't find it? It is
near the top of the image, to the upper right of Gamma Cassiopeia.
Ann
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Re: APOD: The W in Cassiopeia (2016 Mar 18)

Post by starsurfer » Mon Mar 21, 2016 2:51 pm

Ann wrote:
starsurfer wrote:
Ann wrote:I don't have my software here, but there is a soft reddened patch to the left of Caph. Can anyone tell me what it is?

Ann
This is the irregular dwarf galaxy IC 10, a nice closeup by NOAO. Other objects of interest in this image include the red planetary nebula Sh2-188 to the left of NGC 457. Ken Crawford has an excellent closeup image.
Above Ruchbah is the starforming region Sh2-187, an image by Tero Turunen.
The clusters between Ruchbah and Segin include NGC 663 and NGC 654 as well as a few others. Thomas Davis has a nice overview of this area.
The small blue reflection to the south of Caph is vdB1, a rare closer view by Adam Block.

Finally I propose a treasure hunt, somewhere in the image is the Sailboat Cluster (NGC 225). Can you find it? To give you a clue, a nice image by Antonio Sánchez.

An interesting note, this particular mosaic was actually released quite a few years ago.

Cassiopeia is one of my favourite constellations and I always see it's W instantly in the autumn and winter night sky. It also has a fantastic menagerie of deep sky objects for telescopic exploration by visual observers and astrophotographers.
Thanks, starsurfer! :D I thought that might be IC 10, but I wasn't sure.

Thanks for your great links. NGC 663 looks quite impressive in Thomas Davis's image, and that amazing little convoluted knot of gas and dust in Adam Block's image is just wonderful.

I couldn't find the Sailboat Cluster, so I cheated and asked my software to find NGC 225. Indeed, it does look quite sailboat-y!

Can't find it? It is
near the top of the image, to the upper right of Gamma Cassiopeia.
Ann
You cheated! I was going to give you a special prize and I think I will still give it you since you're lovely Ann!