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APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 5:06 am
by APOD Robot
Nebulae in the Northern Cross
Explanation: Explore a beautiful and complex region of nebulae strewn along the plane of our
Milky Way Galaxy in this widefield skyscape. The image emphasizes cosmic gas clouds in a 25 by 25 degree view centered on the Northern Cross, the famous
asterism in the constellation Cygnus. Bright, hot, supergiant
star Deneb at the top of the cross,
Sadr near the center, and beautiful
Albireo run diagonally through the scene. Popular telescopic tour destinations such as the
North America and
Pelican emission regions, the
Butterfly Nebula (IC 1318), and the
Crescent and
Veil nebulae can be identified by placing your cursor over the image. Silhouetted by the glowing
interstellar clouds and crowded star fields, the dark
Northern Coal Sack also stands out, part of a series of obscuring dust clouds forming the
Great Rift in the Milky Way. These Northern Cross nebulosities are all located about 2,000 light-years away. Along with the Sun, they lie within the
Orion spiral arm of our galaxy.
[/b]
NGC 6888: A Wolf-Rayet in swan's clothing.
Posted: Fri Nov 19, 2010 6:49 am
by neufer
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 12:58 pm
by bystander
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 1:12 pm
by Redbone
It looks like a reflection on a lake.
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 1:47 pm
by biddie67
Awesome photo!! As a person new to sky-watching, I really appreciate two items included in the description since I have struggled to figure out what feature is outside the Milky Way or located where inside the Milky Way.
Both the overlay and the "Orion spiral arm" link were very helpful. Thanks.
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 2:06 pm
by orin stepanek
Cool photo! I couldn't look up into the sky and find the Northern Cross. My eye's just aren't good enough to make out the star pattern of this constellation.
Thanks
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 4:05 pm
by neufer
http://en.wikipedia.org/wiki/Kepler_Mission wrote:
<<The Kepler Mission is a NASA space observatory designed to discover Earth-like planets orbiting other stars. The spacecraft was launched on March 7, 2009. With a planned mission lifetime of at least 3.5 years, Kepler uses a photometer developed by NASA to continuously monitor the brightness of over 145,000 main sequence stars in a fixed field of view. The data collected from these observations will be analyzed to detect periodic fluctuations that indicate the presence of extrasolar planets (planets outside our solar system) that are in the process of crossing the face of other stars. The Kepler Mission is currently in active operation, with the first main results announced on 4 January 2010. As expected, the initial discoveries were all short-period planets, with longer period planets expected later. The first six weeks of data revealed five previously unknown planets, all very close to their stars. Among the notable results are one of the least dense planets yet found, and two low-mass white dwarf stars that were initially reported as being members of a new class of stellar objects.>>
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 4:38 pm
by raybun
When you have an APOD that requires a mouse over event like this one has, why can't you remove the pop up from the code when someone puts thier mouse over the APOD image. It's quite annoying at times. Just my 2 cents...
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 4:52 pm
by Chris Peterson
raybun wrote:When you have an APOD that requires a mouse over event like this one has, why can't you remove the pop up from the code when someone puts thier mouse over the APOD image. It's quite annoying at times. Just my 2 cents...
What you are seeing is the ALT text for the image, which is REQUIRED by web standards. The problem is, you should not be seeing it as a popup. This indicates you are using a non-compliant browser, such as Internet Explorer. If you view the APOD with a fully compliant browser like Firefox, there will be no popup of this information unless you have the display of images disabled.
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 7:57 pm
by friarslantern
I don't remember seeing so much red in the night sky across such a large area. Could this photo be color-enhanced, or am I mistaken?
Tim Reeves,
Berkeley, Calif.
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Fri Nov 19, 2010 9:32 pm
by biddie67
The wiki article about the Kepler Mission was interesting. It seemed to be saying that altho' the area that the cameras are pointing are considered rich in possibilites for locating exoplanets, the greater advantages for pointing in that direction was the many logistical pluses for maintaining the steadiness of the cameras in orbit.
Thanks .....
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Sat Nov 20, 2010 5:51 am
by Ann
friarslantern wrote:I don't remember seeing so much red in the night sky across such a large area. Could this photo be color-enhanced, or am I mistaken?
Tim Reeves,
Berkeley, Calif.
This picture is strongly hydrogen alpha enhanced, to bring out all the emission nebulosity that exists in this part of the sky, and which is normally much too faint and tenuous to show up in photographs.
I think that this part of the sky, the Cygnus region, is where inner spiral arms "bend inwards", so that we see emission nebulae at many different depths along our line of sight right here. I think that this part of the sky is where we find really massive star forming regions of our galaxy, but deeper inside the disk and closer to the center than we are. I think that Cygnus OB2 and Cygnus OB5 may be examples of such star forming regions.
Ann
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Sat Nov 20, 2010 7:54 am
by geissi
Hi,
I'm Rolf, author of the Cygnus-APOD.
Thanks a lot for your kind replies.
Could this photo be color-enhanced, or am I mistaken?
This image is strongly color-enhanced by using a slightly modified tone-mapping method by J-P Metsaväinio.
The RGB-image only was used for star color enhancement.
All nebula-colors have been created out of b/w narrowband subframes.
As I'm imaging from a small balcony with heavy light-pollution, that's the only way to
obtain deep nebula images - but this works fine.
The mapping was:
H-alpha = light-red
OIII = cyan
SII = deep red
RGB = natural color only for the stars
Here's some more data:
http://www.stern-fan.de/Seiten/galerie_ ... -80mm.html
Regards
Rolf Geissinger
Remseck, Germany
http://www.stern-fan.de
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Sat Nov 20, 2010 1:47 pm
by DavidLeodis
Excellent image, to which the annotated version was very useful as I doubt I would have located some of the objects. The Northern Coal Sack is however not marked on the annotated version, so am I right in thinking it is the darkish area just to the right of Deneb
Thanks for any help.
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Sat Nov 20, 2010 3:25 pm
by neufer
DavidLeodis wrote:
Excellent image, to which the annotated version was very useful as I doubt I would have located some of the objects. The Northern Coal Sack is however not marked on the annotated version, so am I right in thinking it is the darkish area just to the right of Deneb
Thanks for any help.
Butterfly coal miners
kerosene lamp
Yes. The Butterfly is hovering over The Northern Coal Sack.
http://apod.nasa.gov/apod/ap070920.html
http://apod.nasa.gov/apod/ap031023.html
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Sat Nov 20, 2010 5:45 pm
by DavidLeodis
neufer wrote:DavidLeodis wrote:
Excellent image, to which the annotated version was very useful as I doubt I would have located some of the objects. The Northern Coal Sack is however not marked on the annotated version, so am I right in thinking it is the darkish area just to the right of Deneb
Thanks for any help.
Butterfly coal miners
kerosene lamp
Yes. The Butterfly is hovering over The Northern Coal Sack.
http://apod.nasa.gov/apod/ap070920.html
http://apod.nasa.gov/apod/ap031023.html
Thanks for your help neufer, which is appreciated.
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Sun Nov 21, 2010 6:09 pm
by Guest
Do you suppose technology exists to manufacture a pair of glasses, or binoculars, that could "transform" the near IR and UV waves into human visible light so we could "see" the colors and enjoy the reds, blues, dust, etc. live?
Re: APOD: Nebulae in the Northern Cross (2010 Nov 19)
Posted: Sun Nov 21, 2010 6:45 pm
by BMAONE23
Guest wrote:Do you suppose technology exists to manufacture a pair of glasses, or binoculars, that could "transform" the near IR and UV waves into human visible light so we could "see" the colors and enjoy the reds, blues, dust, etc. live?
Probably not. It takes
Time to gather enough light to begin to see these structures and anything Hand Held wouldn't be absolutely still enough, or focused on and following a single point in space, to allow for a 15/30/60 second refresh rate to begin to see the details of these structures. Although it would be a great invention, I don't think you would get the result you desire as our eyes refresh the light gathered and sent to our brains 30 times a second. That is just too fast to allow for viewing these fine structures through lenses alone.
You could take a telescope and direct the eyepiece view to a CCD that is hooked directly to a computer for processing and display. With a computerized tracking mount, you could follow a stellar objects slow path accross the sky allowing the CCD to gather the light (through any desired filters) and display the image directly on the moniter.
Probably the closest to your idea though others on this board might have other ideas or methods
Another option might be to take the same computer operated tracking mount and attach a digital camera to it instead. Place the appropriate filter(s) over the lens. Use a cable control remote shutter device and a USB cable to allow direct viewing from the lens through a computer & moniter