Page 1 of 1

APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 4:05 am
by APOD Robot
Image Portrait of NGC 281

Explanation: Look through the cosmic cloud cataloged as NGC 281 and it's almost easy to miss stars of open cluster IC 1590. But, formed within the nebula, that cluster's young, massive stars ultimately power the pervasive nebular glow. The eye-catching shapes looming in this portrait of NGC 281 are sculpted columns and dense dust globules seen in silhouette, eroded by intense, energetic winds and radiation from the hot cluster stars. If they survive long enough, the dusty structures could also be sites of future star formation. Playfully called the Pacman Nebula because of its overall shape, NGC 281 is about 10,000 light-years away in the constellation Cassiopeia. This composite image was made through narrow-band filters, but combines emission from the nebula's hydrogen, sulfur, and oxygen atoms in a visible spectrum palette. It spans over 80 light-years at the estimated distance of NGC 281.

<< Previous APODDiscuss Any APOD Next APOD >>
[/b]

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 4:09 am
by mexhunter
A fantastic image of J-P Metsävainio, excellent astrophotographer of narrow band.
Greetings!

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 4:17 am
by neufer

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 4:41 am
by Beyond
The IC 1590 harvard.edu link doesn't connect. I did however, get to see pac-man get Googled er, gobbled up. :lol:

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 9:15 am
by bactame
Pacman's eyeball is nicely defined in this image and his tongue is almost metaphorical.

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 10:47 am
by Indigo_Sunrise
Beyond wrote:I did however, get to see pac-man get Googled er, gobbled up. :lol:
I didn't. :( (It's blocked here.) But I will be home soon, so I'll see it there.

Beautiful image. I really enjoy images featuring NCG's, IC's, M(essier)'s, MyCn18's....
It seems to be a veritable alphabet soup up in the skies! :lol:


Always interesting!

8-)

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 1:19 pm
by orin stepanek
Very nice! Loved today's APOD. 8-) When my kids were young, the Pacman game was one of there favorites! :)

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 7:47 pm
by Wolf kotenberg
It is as cool as looking into a microscope and seeing tiny wiggly things for the first time. Except this is a macroscope and this human becomes insignificant when facing this gigantic maelstrom

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 10:31 pm
by NoelC
What a simply gorgeous, clean, high resolution image, with wonderful texture. Well done, J-P!

-Noel

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 11:11 pm
by racerguy76
So if you were actually in the cloud would you see the colors all around you or would you not notice once your that close to it? Could you even get that close and stay alive?

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Thu Aug 25, 2011 11:19 pm
by Chris Peterson
racerguy76 wrote:So if you were actually in the cloud would you see the colors all around you or would you not notice once your that close to it? Could you even get that close and stay alive?
This object is far too dim to show any color to the human eye. If you were inside it, you wouldn't even be aware of it, except as a very slight increase in the background glow of the sky if you were in an emission zone, or a very slight decrease if you were in dust. Keep in mind that even the densest parts of this cloud constitute a harder vacuum than we can achieve in a laboratory, except at a microscopic scale.

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Fri Aug 26, 2011 12:03 am
by Wladim
Retrato de NGC 281
La fotografía como el comentario son excelentes para los que no sabemos nada sobre el espacio.
Los felicito y les deseo éxitos en sus labores tan profesionales.

Google translate wrote:NGC 281 portrait photography and commentary are excellent for those who know nothing about space. I congratulate them and wish them success in their work as professionals.

This is an English only forum. Please read the Rules.

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Fri Aug 26, 2011 3:21 am
by alter-ego
Chris Peterson wrote:
racerguy76 wrote:So if you were actually in the cloud would you see the colors all around you or would you not notice once your that close to it? Could you even get that close and stay alive?
This object is far too dim to show any color to the human eye. If you were inside it, you wouldn't even be aware of it, except as a very slight increase in the background glow of the sky if you were in an emission zone, or a very slight decrease if you were in dust. Keep in mind that even the densest parts of this cloud constitute a harder vacuum than we can achieve in a laboratory, except at a microscopic scale.
For Earth, I think the Gum Nebula is a good example of this sense of immersion. Although it is a much larger emission nebula, and we are also are not in it, the subtended angle is very large (~40°) leading to a brightness not visible by eye, but photographically it can be captured.

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Fri Aug 26, 2011 3:32 am
by Ann
This is a beautiful APOD. As for the color of the gases, we couldn't see them, because the gases are far too tenuous. I like alter-ego's comparison with the Gum Nebula.

We could, however, detect a blue tinge in the light from the brightest star, if we were at just the right distance from it. The right distance would be where the star is bright enough to stimulate the color response of our retinas, but not so bright that it was uncomfortable to look at.

The bright central star, HD 5005, is a very hot star of spectral class O5.5. It is reddened by the gases surrounding it, but still it looks relatively blue, with an apparent color index of 0.101. If we could assess its (apparent) color at all, it would look much bluer than it does in today's APOD, where the color of the star is affected by the narrowband imaging.

Ann

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Sun Aug 28, 2011 11:14 pm
by NoelC
I've often wondered whether the Integrated Flux Nebula that we can just about detect up near Polaris is one that we're inside...

-Noel

NASA IOTD: NGC 281: The Pacman Nebula (2011 Sep 28)

Posted: Wed Sep 28, 2011 4:42 pm
by bystander
NGC 281: Living the High Life
NASA SAO CXC | 2011 Sept 28

NGC 281: Living the High Life
NASA JPL-Caltech Spitzer | 2011 Sept 28

NGC 281: The Pacman Nebula
NASA IOTD | 2011 Sept 28
High-mass stars are important because they are responsible for much of the energy pumped into our galaxy over its lifetime. Unfortunately, these stars are poorly understood because they are often found relatively far away and can be obscured by gas and dust. The star cluster NGC 281 is an exception to this rule. It is located about 6,500 light years from Earth and, remarkably, almost 1,000 light years above the plane of the galaxy, giving astronomers a nearly unfettered view of the star formation within it.

This composite image of NGC 281 contains X-ray data from Chandra, in purple, with infrared observations from Spitzer, in red, green, blue. The high-mass stars in NGC 281 drive many aspects of their galactic environment through powerful winds flowing from their surfaces and intense radiation that creates charged particles by stripping electrons off atoms. The eventual deaths of massive stars as supernovas will also seed the galaxy with material and energy.

NGC 281 is known informally as the "Pacman Nebula" because of its appearance in optical images. In optical images the "mouth" of the Pacman character appears dark because of obscuration by dust and gas, but in the infrared Spitzer image the dust in this region glows brightly.

NGC 281 is typically divided into two subregions: the region in the upper middle of the image, which is surrounded by the purple 10-million-degree gas, and a younger region in the lower part of the image. There is evidence that the formation of a cluster, appearing in a beige cloud to the lower right, was triggered by a previous generation of star formation. Also, astronomers have found some isolated star formation on the left side of the image that appears to have been occurring at the same time as star formation in other regions of the cluster. This supports the idea that something externally triggered the "baby boom" of stars in NGC 281.

Re: APOD: Portrait of NGC 281 (2011 Aug 25)

Posted: Wed Sep 28, 2011 4:53 pm
by owlice
Wow, that's gorgeous! I think that needs to be on a submissions thread!!