Found images: 2015 May

[Sandgirl]

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Have you seen a great image or video somewhere that you think would make a great APOD? Nominate it for APOD! Please post as much information here as you have about the image/video with a link to any source(s) for it you know of here, and the editors will take a look.

When posting the image itself, please do not post anything larger than a thumbnail here; please honor the copyright holder's copyright.

Please keep hotlinked images under 400K.

Thank you!

[starsurfer]

Trifid Nebula (M20)
http://www.cosmicphotos.com/gallery/ima ... lbum_id=11
Copyright: Jason Jennings

[starsurfer]

NGC 3521
http://bf-astro.com/ngc3521/ngc3521.htm
Copyright: Bob Franke

[starsurfer]

Hen 2-111
http://www.pbase.com/tango33/image/159139261
Copyright: Kfir Simon

[bystander]

A Hole in the Sky (LDN 1774)
ESO Picture of the Week | 2015 May 04

[attachment=0]potw1518a[1].jpg[/attachment]

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Rather than showing spectacular objects, some of the most surprising images of the Universe instead focus on emptiness. This new image from the 2.2-metre MPG/ESO telescope shows dark tentacles swirling outwards from a dark, blank spot of space in the centre of the frame, particularly conspicuous against the dense peppering of bright gold and red stars across the rest of the image.

This region is not a hole in the cosmos, or an empty patch of sky. The dark lanes are actually made up of thick, opaque dust lying between us and the packed star field behind it. This obscuring dust forms part of a dark molecular cloud, cold and dense areas where large quantities of dust and molecular gas mingle and block the visible light emitted by more distant stars.

It is still unclear how these clouds form, but they are thought to be the very early stages of new star formation — in the future, the subject of this image may well collapse inwards on itself to form a new star system.

Although the cloud in this image is a fairly anonymous resident of the nearby Universe — catalogued as LDN 1774 — one of the most famous examples of a molecular cloud is the very similar Barnard 68, which lies some 500 light-years away from us. Barnard 68 has been observed extensively using ESO telescopes, both in visible (eso9924) and infrared light (eso9934, eso0102). As shown in these different images, it is possible to probe through dark cosmic dust using infrared light, but visible-light observations such as those shown in this VLT image cannot see beyond the smokescreen.

This image was taken by the Wide Field Imager, an instrument mounted on ESO’s 2.2-metre MPG/ESO telescope at La Silla, Chile.

[bystander]

The Peculiar Asymmetry of NGC 949
ESA Hubble Picture of the Week | 2015 May 04

[i][b]Credit: ESA/Hubble & NASA[/b][/i]

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This image provides the clearest ever view of galaxy NGC 949, which lies over 30 million light-years away in the constellation of Triangulum. The galaxy has an unusual shape, made more obscure due to its inclination. From our point of view, it is difficult to discern exactly what type of galaxy NGC 949 is, but it is certainly a disc galaxy of some kind, most likely a spiral.

NGC 949 was first discovered by Sir William Herschel on 21 September 1786, using an 18.7-inch reflecting telescope. The galaxy was one of about 3000 objects Herschel catalogued as "nebulae" during an intense and systematic deep sky survey, the results of which eventually formed the bulk of the New General Catalogue (NGC).

Taken with Hubble’s Advanced Camera for Surveys (ACS), this new image shows extraordinary detail. This detail allows us to see a strange asymmetric alignment in the dark lanes of dust that snake across the galaxy. The top-right half of the galaxy appears considerably more marbled with dust in this image; a curious observation explained by stars tending to favour locations towards the centre of a galaxy, and dust preferring almost invariably to reside along the galactic plane.

When a galaxy is inclined as NGC 949 is, some regions — in this case the top-right — are tipped towards us and the light from the stars we see in these regions has had to travel through more dust. This causes the light to appear redder — the result of the same process that gives the sun’s light a red hue at dusk — or else disappear entirely, making the dust appear more prominent on that side of the galaxy.

In the part tipped away from us, the light from the stars has had to pass through much less dust to reach us, so it appears brighter, and the dust is much less prominent.

Were it possible to view NGC 949 from the opposite side, the apparent alignment of the dust would be reversed.

The scientific advantages of this effect were recently displayed in suitably stunning style in the M31 PHAT mosaic, which allowed astronomers to produce a partial three-dimensional dust map of M31 four times clearer than any previously attempted.

[starsurfer]

A Hole in the Sky (LDN 1774)
ESO Picture of the Week | 2015 May 04

[attachment=0]potw1518a[1].jpg[/attachment]

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Rather than showing spectacular objects, some of the most surprising images of the Universe instead focus on emptiness. This new image from the 2.2-metre MPG/ESO telescope shows dark tentacles swirling outwards from a dark, blank spot of space in the centre of the frame, particularly conspicuous against the dense peppering of bright gold and red stars across the rest of the image.

This region is not a hole in the cosmos, or an empty patch of sky. The dark lanes are actually made up of thick, opaque dust lying between us and the packed star field behind it. This obscuring dust forms part of a dark molecular cloud, cold and dense areas where large quantities of dust and molecular gas mingle and block the visible light emitted by more distant stars.

It is still unclear how these clouds form, but they are thought to be the very early stages of new star formation — in the future, the subject of this image may well collapse inwards on itself to form a new star system.

Although the cloud in this image is a fairly anonymous resident of the nearby Universe — catalogued as LDN 1774 — one of the most famous examples of a molecular cloud is the very similar Barnard 68, which lies some 500 light-years away from us. Barnard 68 has been observed extensively using ESO telescopes, both in visible (eso9924) and infrared light (eso9934, eso0102). As shown in these different images, it is possible to probe through dark cosmic dust using infrared light, but visible-light observations such as those shown in this VLT image cannot see beyond the smokescreen.

This image was taken by the Wide Field Imager, an instrument mounted on ESO’s 2.2-metre MPG/ESO telescope at La Silla, Chile.

One advantage amateur astrophotographers is being able to photograph areas with a very large field of view. The ESO image shows only a small part of the entire Pipe Nebula complex but can be seen in its entirety in this image by Jason Jennings.

[starsurfer]

Seagull Nebula (IC 2177) widefield
https://www.flickr.com/photos/deepskycolors/13955150820
Copyright: Rogelio Bernal Andreo

[starsurfer]

NGC 6914
http://bf-astro.com/ngc6914rcos/ngc6914.htm
Copyright: Bob Franke

http://bf-astro.com/ngc6914fsq/ngc6914fsq.htm

[starsurfer]

Cave Nebula (Sh2-155)
http://www.astrosurf.com/ilizaso/orriak ... Q_U16m.htm
Copyright: Iñaki Lizaso

[starsurfer]

NGC 2451 and NGC 2477
http://www.astrobin.com/149378/
Copyright: Roberto Colombari

[Sandgirl]

Colourful Moon
Copyrights: Bartosz Wojczyński
Suggested by: Hanna Czempiel and Marek Substyk
http://petapixel.com/2015/05/04/this-hi ... tographer/
http://albireo.vipower.pl/bar/gallery/f ... siezyc.jpg

ISS and Jupiter
Copyrights: Michele Brusa
Suggested by: Marco Delbo

[starsurfer]

Sh2-82
http://www.noao.edu/image_gallery/html/im1246.html
Copyright: T.A. Rector (University of Alaska Anchorage) and H. Schweiker (WIYN and NOAO/AURA/NSF)

Somewhere in this image is a tiny yellow reflection nebula!

[starsurfer]

B150
http://www.astrobin.com/80832/
Copyright: Alessandro Falesiedi

[bystander]

Iridescent Nightscape over La Silla
ESO Picture of the Week | 2015 May 11

[b][i]Credit: ESO/[/i][/b][url=https://www.facebook.com/yuribeletskyphoto][b][i]Yuri Beletsky[/i][/b][/url]

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This image shows ESO’s La Silla Observatory perched on the outskirts of the Chilean Atacama Desert and cloaked in an iridescent sky. Deep reddish hues permeate the right side of the frame and give way to the Milky Way, which can be seen with stunning clarity from La Silla, a location boasting some of the darkest and clearest night skies on Earth. The red and greenish-yellow glow is caused by airglow — a glow caused by the Earth’s atmosphere that is usually only seen from space, or at very dark locations.

Hogging the limelight in this frame is the silver dish in the foreground — the Swedish–ESO Submillimetre Telescope (SEST). Although it was decommissioned in 2003 and is no longer in service SEST still provides a picturesque target for keen photographers as it reflects the bright lights and colours of the skies above.

In the background of the image is the rounded dome that houses the ESO 3.6-metre telescope, host to the High Accuracy Radial velocity Planet Searcher instrument (HARPS). HARPS is the world's foremost exoplanet hunter, and has successfully found more low-mass exoplanets than any other planet hunter to date.

This image was taken by ESO Photo Ambassador Yuri Beletsky, who takes astronomical images like these during his spare time while working as an astronomer at ESO’s La Silla Paranal Observatory.

[bystander]

Galactic Onion (NGC 3923)
ESA Hubble Picture of the Week | 2015 May 11

[b][i]Credit: ESA/Hubble & NASA - Acknowledgement: Judy Schmidt[/i][/b]

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The glowing object in this image is an elliptical galaxy called NGC 3923. It is located over 90 million light-years away in the constellation of Hydra.

NGC 3923 is an example of a shell galaxy where the stars in its halo are arranged in layers.

Finding concentric shells of stars enclosing a galaxy is quite common and is observed in many elliptical galaxies. In fact, every tenth elliptical galaxy exhibits this onion-like structure, which has never been observed in spiral galaxies. The shell-like structures are thought to develop as a consequence of galactic cannibalism, when a larger galaxy ingests a smaller companion. As the two centres approach, they initially oscillate about a common centre, and this oscillation ripples outwards forming the shells of stars just as ripples on a pond spread when the surface is disturbed.

NGC 3923 has over twenty shells, with only a few of the outer ones visible in this image and its shells are much more subtle than those of other shell galaxies. The shells of this galaxy are also interestingly symmetrical, while other shell galaxies are more skewed.

A version of this image was entered into the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt.

http://asterisk.apod.com/viewtopic.php?p=220455#p220455

[starsurfer]

Galactic Onion (NGC 3923)
ESA Hubble Picture of the Week | 2015 May 11

[b][i]Credit: ESA/Hubble & NASA - Acknowledgement: Judy Schmidt[/i][/b]

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The glowing object in this image is an elliptical galaxy called NGC 3923. It is located over 90 million light-years away in the constellation of Hydra.

NGC 3923 is an example of a shell galaxy where the stars in its halo are arranged in layers.

Finding concentric shells of stars enclosing a galaxy is quite common and is observed in many elliptical galaxies. In fact, every tenth elliptical galaxy exhibits this onion-like structure, which has never been observed in spiral galaxies. The shell-like structures are thought to develop as a consequence of galactic cannibalism, when a larger galaxy ingests a smaller companion. As the two centres approach, they initially oscillate about a common centre, and this oscillation ripples outwards forming the shells of stars just as ripples on a pond spread when the surface is disturbed.

NGC 3923 has over twenty shells, with only a few of the outer ones visible in this image and its shells are much more subtle than those of other shell galaxies. The shells of this galaxy are also interestingly symmetrical, while other shell galaxies are more skewed.

A version of this image was entered into the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt.

I'm glad that Judy Schmidt processed this as well as there being an official release! I don't know why there aren't any deep amateur images, they would show the full extent of the system of shells associated with this shell elliptical galaxy.

[starsurfer]

NGC 247
http://www.billionsandbillions.com/ngc_247.html
Copyright: Warren Keller/SSRO

Click to view full size image

[starsurfer]

RCW 27 and RCW 32
http://www.tvdavisastropics.com/astroim ... 000021.htm
Copyright: Tom Davis

[geckzilla]

I don't know why there aren't any deep amateur images, they would show the full extent of the system of shells associated with this shell elliptical galaxy.

They're not appealing at first. I have to say that their subtle mystique is somewhat mesmerizing if given a chance. I have grown quite fond of them.

[starsurfer]

I don't know why there aren't any deep amateur images, they would show the full extent of the system of shells associated with this shell elliptical galaxy.

They're not appealing at first. I have to say that their subtle mystique is somewhat mesmerizing if given a chance. I have grown quite fond of them.

I'm glad to hear of your change of heart! I just love tidal features in galaxies (and obviously haloes in planetary nebulae) and shell ellipticals are really cool! My favourites are ones that have multiple inner shells and a few diffuse outer ones as well such as NGC 1344. The HST isn't best suited to most of the large NGC ones, it does a great job on the smaller galaxies. The shell system of NGC 3923 extends for nearly one degree!!! Also one reason for the lack of amateur images is simply that people don't know about them, the majority of amateur astrophotographers don't go digging through scientific papers to find new interesting imaging targets.

[starsurfer]

Sh2-216 and Sh2-221
http://www.capella-observatory.com/Imag ... 21_216.htm
Copyright: Stefan Binnewies

This widefield image beautifully illustrates the two main types of stardeath. On the right is the planetary nebula Sh2-216 in the constellation of Perseus, produced by the death of a small sized star with 0.8-8 stellar masses. It also holds the distinction of being both the closest planetary nebula with a distance of 420 light years as well as the largest angular size of 100x90 arcminutes. It's intrinsic size is approximately 12 light years. It was discovered in 1954 and identified as a planetary nebula in 1985. It is also one of the oldest planetary nebulae in the Milky Way with an estimated age of approximately 350,000 years.

On the left is the supernova remnant Sh2-221 in the neighbouring constellation of Auriga, produced by the death of a large star with more than 8 stellar masses. It is also known as HB 9 named after its radio emission.

[starsurfer]

Heart Nebula (IC 1805) closeup
http://www.astrobin.com/132787/D/
Copyright: Enrico Scheibel

[starsurfer]

NGC 3201
http://www.astrophoton.com/NGC3201.htm
Copyright: CEDIC
Processing: Bernhard Hubl

Click to view full size image

[starsurfer]

LDN 1622
http://www.glitteringlights.com/Images/ ... zPcCD3t/X3
Copyright: Marco Lorenzi