APOD: A 212-Hour Exposure of Orion (2015 Nov 23)

[APOD Robot]

A 212-Hour Exposure of Orion

Explanation: The constellation of Orion is much more than three stars in a row. It is a direction in space that is rich with impressive nebulas. To better appreciate this well-known swath of sky, an extremely long exposure was taken over many clear nights in 2013 and 2014. After 212 hours of camera time and an additional year of processing, the featured 1400-exposure collage spanning over 40 times the angular diameter of the Moon emerged. Of the many interesting details that have become visible, one that particularly draws the eye is Barnard's Loop, the bright red circular filament arcing down from the middle. The Rosette Nebula is not the giant red nebula near the top of the image -- that is a larger but lesser known nebula known as Lambda Orionis. The Rosette Nebula is visible, though: it is the red and white nebula on the upper left. The bright orange star just above the frame center is Betelgeuse, while the bright blue star on the lower right is Rigel. Other famous nebulas visible include the Witch Head Nebula, the Flame Nebula, the Fox Fur Nebula, and, if you know just where to look, the comparatively small Horsehead Nebula. About those famous three stars that cross the belt of Orion the Hunter -- in this busy frame they can be hard to locate, but a discerning eye will find them just below and to the right of the image center.

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[Beyond]

It shows up rather vividly on the Windows 10 i got yesterday.

[ta152h0]

what could the ancient Egyptians havepossibly seen in this ?

[neufer]

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what could the ancient Egyptians havepossibly seen in this ?

Sah.

[No one in particular]

Ok, this may sound like a silly question. But if it took 212 hours to show the matter that is evident in this composite photo, matter that otherwise would not be seen, would this be considered 'dark matter'? Also, noticing that there are some dim features in this image, I wonder what an image with 2000 hours would show?

It is amazing what we cannot see....

[Ann]

Oh wow, oh wow, oh wow!!!!

As a color nerd I find this explosion of color so beautiful that it would be given pride of place in the New York Museum of Modern Art if I had any say in the matter!

There are so many fantastic details in the picture that I don't know where to start. Note, however, that golden-orange Betelgeuse seems to be connected to Barnard's Loop via a stubby red "arm", making Betelgeuse itself look a little like a golden "fist" at the end of that arm. Round red Lambda Orionis Nebula is the big round "head" of this "man" (or woman?).

Note that we can see some red emission nebulosity to the right (west) of Alnilam, the middle star in Orion's Belt, and to the left (east) of blue supergiant Rigel. We can almost feel the power of Rigel and see how it has shed layers of gas before, which are now being illuminated by the star itself.

Note the Witch Head Nebula. But note, too, that there is another, reddish "Witch Head nebula" to the upper right of the real one. Note another dust sculpture, looking like a man with a big nose, to the upper left of the Witch Head Nebula.

Also note bright bluish reflection nebula M78 in a bright part of Barnard's Loop, to the upper right of the Horsehead Nebula. And to the upper right of M78 is an intricately shaped dark dust pillar, a convoluted relative of the famous "Pillars of Creation" - or even a relative of the Horsehead Nebula itself. The way this dark dust pillar pokes its head up over a wall of red nebulosity is also reminiscent of the Horsehead Nebula.

And note how the bright Rosette Nebula seems to be connected to a string of nebulas above and below it.

What a truly fantastic and stunningly beautiful image!!!

Ann

[Ann]

Ok, this may sound like a silly question. But if it took 212 hours to show the matter that is evident in this composite photo, matter that otherwise would not be seen, would this be considered 'dark matter'? Also, noticing that there are some dim features in this image, I wonder what an image with 2000 hours would show?

It is amazing what we cannot see....

Astronomers believe that dark matter is truly dark. That is to say that even a 2,000-hour exposure would show no trace of it, and not a 200,000-hour exposure either.

Matter that can be revealed in long exposures is not dark matter at all. That is just ordinary matter that gives off very little light.

Ann

[Roger]

The star labeled Meissa is Lambda Orionis, and I have never before heard the Orion Bubble (which is the large red circular area around Meissa, and is here labeled 'Lambda Orionis') confused with the star. But I've only been paying attention for 55 years, so maybe I'm a newbie.

[Ann]

The star labeled Meissa is Lambda Orionis, and I have never before heard the Orion Bubble (which is the large red circular area around Meissa, and is here labeled 'Lambda Orionis') confused with the star. But I've only been paying attention for 55 years, so maybe I'm a newbie.

The nebula is not normally called the Orion Bubble, but the Lambda Orionis Nebula. I mentioned it in a post just two days ago.

Ann

[heehaw]

I've been an astronomer since about age 10, but I didn't know any other astronomers, and I pronounced it "orrey-on" instead of O'Ryan.

[RedFishBlueFish]

Orionid Storms.

Magnificent!

[Whiskybreath]

Superb. That year must have been a trial, though.

[tetrodehead]

What a follow-up to yesterdays APOD!
Thanks for this magnificant vista.

[Chris Peterson]

Matter that can be revealed in long exposures is not dark matter at all. That is just ordinary matter that gives off very little light.

And this example doesn't even give off little light. Anything visible in a mere few hundred hours of exposure with a small telescope is intrinsically bright. And that's not considering all the "light" given off at wavelengths not being collected here (i.e. most of the electromagnetic spectrum!)

[Ron-Astro Pharmacist]

I see Geck has labeled Cursa (β Eridani)in today's giant mass of beautiful data. Appropriately named the Footstool of the Central One, fictionally, its planets may appear like this. Artistically inclined may wish to contribute their renditions to the site. It may help budding minds image places we'll not likely see.

Opposingly, as much as is going on is today's APOD, Eridanus's river leads us to one of the emptiest places in the universe.

[pmaison]

just stunning... If APOD pix were baseball plays, this 212 hr beauty is a bases-clearing grand slam that sailed high over the bleachers, cleared the parking lots and is somewhere floating out in the bay. Thanks all.

[starsurfer]

What a joy it is to "surf" through the full resolution version of this magnificent vista! The brightness and contrast shows the popular well known nebulae very well but also makes fainter obscure nebulae stand out. Some highlights include the purple nebula NGC 2170 in Monoceros near Barnard's Loop, the strange filamentary emission nebula Sh2-260 in Orion and the planetary nebula WDHS 1 (which some know as WeDe 1) as well as the bright blob of the small planetary nebula Abell 13. There are also some clusters in this scene, NGC 2141 to the left of Sh2-264 (Lambda Orionis ring) and Berkeley 24 in Monoceros below the trio of emission nebulae below the Rosette Nebula. If you look carefully, some galaxies are also visible in the Eridanus and Monoceros regions. In addition to all this, there are also some uncatalogued nebulae in this scene. Finally, visible as a tiny dot near Barnard's Loop is the previous planetary nebula candidate Teutsch 11, which has just been identified as an ancient nova shell!!

[Boomer12k]

IF you have such a thing as APOD OF THE YEAR....THIS IS IT!!!! In my humble opinion...

Such a broad view of the sky...is this a Mosaic, or 1400 single long shot exposures? Sounds like the latter. Which is AMAZING!!!! When I do my shots, I do maybe 20 single shots, and stack them to keep down some of the "noise" in the photo. Sometimes I get good results with more frames.

This is the single most amazing image of my favorite area, M42 in particular...though not so close up.

Absolutely FANTASTIC JOB!!!!!!!! And worthy of APOD of the Year, if there is such a thing. And I appreciate the time consuming effort.

:---[===] *

[DavidLeodis]

It's a great image.

I must be finally learning things from APODs as even I spotted the Horsehead Nebula before I saw the excellent annotated rollover. <<< There isn't a horse smilie so I used the puppy one instead!

[Ironwood]

Please let a roll over moon size icon be a regular feature at APOD.

[starsurfer]

Such a broad view of the sky...is this a Mosaic, or 1400 single long shot exposures?

This is very likely to be a mosaic of multiple frames with multiple sub-exposures.

[Chris Peterson]

Such a broad view of the sky...is this a Mosaic, or 1400 single long shot exposures?

This is very likely to be a mosaic of multiple frames with multiple sub-exposures.

The image covers approximately 22°x26°. Shot with a STL11K and a 200mm lens, that corresponds to a 3x3 mosaic. The imager's site, however, claims a 3x4 mosaic, which makes sense allowing for a fair degree of overlap (the 200mm Canon lens does not have a geometrically flat field, so edge-to-edge mosaics are difficult). So 1400 images, divided by 12 subframes, divided by 5 filters, averages out to a bit over 20 subs per filter per mosaic section. The total time gives an average of about 10-minute exposures. All sounds pretty reasonable.

[starsurfer]

Such a broad view of the sky...is this a Mosaic, or 1400 single long shot exposures?

This is very likely to be a mosaic of multiple frames with multiple sub-exposures.

The image covers approximately 22°x26°. Shot with a STL11K and a 200mm lens, that corresponds to a 3x3 mosaic. The imager's site, however, claims a 3x4 mosaic, which makes sense allowing for a fair degree of overlap (the 200mm Canon lens does not have a geometrically flat field, so edge-to-edge mosaics are difficult). So 1400 images, divided by 12 subframes, divided by 5 filters, averages out to a bit over 20 subs per filter per mosaic section. The total time gives an average of about 10-minute exposures. All sounds pretty reasonable.

Thanks for taking the time to work this all out!! Also I know some people won't like the high contrast and brightness of this image but it certainly makes the fainter and lesser known nebulae more visible.