Found images: 2016 January

[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]

NGC 6726-7
http://www.starpointing.com/ccd/ngc6726.html
Copyright: Fabian Neyer

[bystander]

Supermassive and Super-hungry
ESA Hubble Picture of the Week | 2016 Jan 04

[img3="Credit: ESA/Hubble & NASA and S. Smartt (Queen's University Belfast)"]http://cdn.spacetelescope.org/archives/ ... w1601a.jpg[/img3][hr][/hr]

This NASA/ESA Hubble Space Telescope image shows the spiral galaxy NGC 4845, located over 65 million light-years away in the constellation of Virgo (The Virgin). The galaxy’s orientation clearly reveals the galaxy’s striking spiral structure: a flat and dust-mottled disc surrounding a bright galactic bulge.

NGC 4845’s glowing centre hosts a gigantic version of a black hole, known as a supermassive black hole. The presence of a black hole in a distant galaxy like NGC 4845 can be inferred from its effect on the galaxy’s innermost stars; these stars experience a strong gravitational pull from the black hole and whizz around the galaxy’s centre much faster than otherwise.

From investigating the motion of these central stars, astronomers can estimate the mass of the central black hole — for NGC 4845 this is estimated to be hundreds of thousands times heavier than the Sun. This same technique was also used to discover the supermassive black hole at the centre of our own Milky Way — Sagittarius A* — which hits some four million times the mass of the Sun (potw1340a).

The galactic core of NGC 4845 is not just supermassive, but also super-hungry. In 2013 researchers were observing another galaxy when they noticed a violent flare at the centre of NGC 4845. The flare came from the central black hole tearing up and feeding off an object many times more massive than Jupiter. A brown dwarf or a large planet simply strayed too close and was devoured by the hungry core of NGC 4845.

[starsurfer]

Sunflower Galaxy (M63)
http://www.spacetelescope.org/images/potw1536a/
Copyright: ESA/Hubble & NASA

[starsurfer]

NGC 602
http://members.pcug.org.au/~stevec/NGC6 ... 3_RC14.htm
Copyright: Steve Crouch

MCSNR J0127-7332 is the supernova remnant below and to the left of NGC 602.

[starsurfer]

NGC 2467
http://www.astro-austral.cl/imagenes/ne ... T/info.htm
Copyright: José Joaquín Pérez/SSRO

[Ann]

Click to view full size image

NGC 4639. Photo: NASA/ESA

As I searched the net for other images of spiral galaxy NGC 4845 (to compare it with the new Hubble image of NGC 4845 that bystander just posted), I found a very elegant Hubble image of another spiral galaxy with a large central black hole. I don't remember seeing this image at Starship Asterisk* before, so I'm posting it here.

Full size can be seen here. Read about the galaxy here.

Ann

[Ann]

Supermassive and Super-hungry
ESA Hubble Picture of the Week | 2016 Jan 04

[img3="Credit: ESA/Hubble & NASA and S. Smartt (Queen's University Belfast)"]http://cdn.spacetelescope.org/archives/ ... w1601a.jpg[/img3][hr][/hr]

This NASA/ESA Hubble Space Telescope image shows the spiral galaxy NGC 4845, located over 65 million light-years away in the constellation of Virgo (The Virgin). The galaxy’s orientation clearly reveals the galaxy’s striking spiral structure: a flat and dust-mottled disc surrounding a bright galactic bulge.

NGC 4845’s glowing centre hosts a gigantic version of a black hole, known as a supermassive black hole. The presence of a black hole in a distant galaxy like NGC 4845 can be inferred from its effect on the galaxy’s innermost stars; these stars experience a strong gravitational pull from the black hole and whizz around the galaxy’s centre much faster than otherwise.

From investigating the motion of these central stars, astronomers can estimate the mass of the central black hole — for NGC 4845 this is estimated to be hundreds of thousands times heavier than the Sun. This same technique was also used to discover the supermassive black hole at the centre of our own Milky Way — Sagittarius A* — which hits some four million times the mass of the Sun (potw1340a).

The galactic core of NGC 4845 is not just supermassive, but also super-hungry. In 2013 researchers were observing another galaxy when they noticed a violent flare at the centre of NGC 4845. The flare came from the central black hole tearing up and feeding off an object many times more massive than Jupiter. A brown dwarf or a large planet simply strayed too close and was devoured by the hungry core of NGC 4845.

A central black hole less than a million times the mass of the Sun is not very supermassive as central black holes go. As the caption said, the central black hole of out own Milky Way is about 4 million times the mass of the Sun. And according to Wikipedia, the supermassive central black hole of the Andromeda galaxy may weigh anything from 30 to 230 million times the mass of our own star.

So the black hole of NGC 4845 is not very supermassive, and the galaxy itself is not extremely large, either. According to Principal Galaxy Catalog, the luminosity of NGC 4845 is about half that of the luminosity of the Milky Way.

But NGC 4845 is strikingly poor in star formation. The picture bystander posted shows just a smattering of blue stars over the entire disk of NGC 4845. It would be very interesting if the central black hole of NGC 4845 is sufficiently active to severely dampen the rate of star formation in this galaxy.

Ann

[starsurfer]

IC 2948
http://www.martinpughastrophotography.id.au
Copyright: Martin Pugh

[starsurfer]

Ced 214 and NGC 7822
http://www.caelumobservatory.com/galler ... abtp.shtml
Copyright: Adam Block and Tim Puckett

Ced 214 is the nebula in the bottom half while NGC 7822 is the nebula at the top.

[starsurfer]

vdB152
http://www.astroimager.net/Page-RHA-CCD-344.html
Copyright: Jim Janusz

The nebula to the right of B175 is the planetary nebula mimic DeHt 5. The arc to the north belongs to G110.3+11.3, a supernova remnant.

[Ann]

NGC 6902

Click to view full size image

I stumbled on this lovely portrait by Rolf Olsen of galaxies in a field of stars as I was googling for images of starfields. The large, delicate spiral is NGC 6902, the yellow edge-on galaxy at 12 o'clock is IC 4946, and the small blue galaxy at 10 o'clock is NGC 6902B.

Full size can be seen here.

Ann

[starsurfer]

Taurus Molecular Cloud
http://www.astrobin.com/228813/
Copyright: Tommy Nawratil

[starsurfer]

LDN 1251
http://bf-astro.com/ldn1251/ldn1251.htm
Copyright: Bob Franke

[starsurfer]

NGC 2174
http://astrophotography.aa6g.org/Astrop ... vs130.html
Copyright: Chuck Vaughn

[starsurfer]

N44
http://www.eso.org/public/images/eso0332a/
Copyright: ESO

[bystander]

Three Pillars of Astronomy
ESO Picture of the Week | 2016 Jan 11

[img3="Credit: ESO/Babak Tafreshi (TWAN)"]http://www.eso.org/public/archives/imag ... w1602a.jpg[/img3][hr][/hr]

This picture, taken at the La Silla Observatory in Chile, shows the full Moon low in the purple sky, a photographer crouching on the rocks, and the New Technology Telescope (NTT) perched on a hilltop. This image depicts the three things we need for observational astronomy: An object to observe, a telescope to observe it, and a person to make sense of the observations.

The Moon is the closest celestial body to Earth and orbits at a distance of 400 000 kilometres as our only natural satellite. Despite the aesthetic glow of the full Moon in this image, the Moon is not a great friend to astronomers. Sunlight that reflects off the lunar surface causes light pollution and makes it harder to observe more distant and very faint objects. Light pollution does not, however, bother the man admiring the view here. This is Babak A. Tafreshi, one of ESO's Photo Ambassadors.

The gap between astronomers and extraterrestrial bodies is bridged by the telescope. In this picture we can see ESO's NTT, a telescope first installed in 1989 and completely upgraded in 1997 in the "NTT-Big Bang". A key feature of the NTT is that it pioneered the use of active optics to adjust the thin telescope mirror so that it is always the optimum shape to form the sharpest images.

[bystander]

A galactic mega-merger
ESA Hubble Picture of the Week | 2016 Jan 11

[img3="Credit: ESA/Hubble & NASA
Acknowledgement: Judy Schmidt"]http://cdn.spacetelescope.org/archives/ ... w1602a.jpg[/img3][hr][/hr]

The subject of this NASA/ESA Hubble Space Telescope image is known as NGC 3597. It is the product of a collision between two good-sized galaxies, and is slowly evolving to become a giant elliptical galaxy. This type of galaxy has grown more and more common as the Universe has evolved, with initially small galaxies merging and progressively building up into larger galactic structures over time.

NGC 3597 is located approximately 150 million light-years away in the constellation of Crater (The Cup). Astronomers study NGC 3597 to learn more about how elliptical galaxies form — many ellipticals began their lives far earlier in the history of the Universe. Older ellipticals are nicknamed “red and dead” by astronomers because these bloated galaxies are not anymore producing new, bluer, stars in ages, and are thus packed full of old and redder stellar populations.

Before infirmity sets in, some freshly formed elliptical galaxies experience a final flush of youth, as is the case with NGC 3597. Galaxies smashing together pool their available gas and dust, triggering new rounds of star birth. Some of this material ends up in dense pockets initially called proto-globular clusters, dozens of which festoon NGC 3597. These pockets will go on to collapse and form fully-fledged globular clusters, large spheres that orbit the centres of galaxies like satellites, packed tightly full of millions of stars.

[starsurfer]

Iris Nebula (NGC 7023)
http://www.astrosurf.com/ilizaso/orriak ... Q_U16m.htm
Copyright: Iñaki Lizaso

This widefield image also includes LBN 468 with Gyulbudaghian's Nebula to the right of the Iris Nebula and the reflection nebula vdB141 to the left.

[Ann]

A galactic mega-merger
ESA Hubble Picture of the Week | 2016 Jan 11

[img3="Credit: ESA/Hubble & NASA
Acknowledgement: Judy Schmidt"]http://cdn.spacetelescope.org/archives/ ... w1602a.jpg[/img3][hr][/hr]

The subject of this NASA/ESA Hubble Space Telescope image is known as NGC 3597. It is the product of a collision between two good-sized galaxies, and is slowly evolving to become a giant elliptical galaxy. This type of galaxy has grown more and more common as the Universe has evolved, with initially small galaxies merging and progressively building up into larger galactic structures over time.

NGC 3597 is located approximately 150 million light-years away in the constellation of Crater (The Cup). Astronomers study NGC 3597 to learn more about how elliptical galaxies form — many ellipticals began their lives far earlier in the history of the Universe. Older ellipticals are nicknamed “red and dead” by astronomers because these bloated galaxies are not anymore producing new, bluer, stars in ages, and are thus packed full of old and redder stellar populations.

Before infirmity sets in, some freshly formed elliptical galaxies experience a final flush of youth, as is the case with NGC 3597. Galaxies smashing together pool their available gas and dust, triggering new rounds of star birth. Some of this material ends up in dense pockets initially called proto-globular clusters, dozens of which festoon NGC 3597. These pockets will go on to collapse and form fully-fledged globular clusters, large spheres that orbit the centres of galaxies like satellites, packed tightly full of millions of stars.

I love that image!

Geck is credited for processing the image, but I'm not absolutely sure that this is Geck's work. I found two images of NGC 3597 processed by Geck on the net, and I'm particularly impressed by the one that shows the entire galaxy, with its huge elliptical shells. In that image you can also see the great brightness difference between the rather small, bright, dusty starforming center and the large, faint, dust-free multiple shells. Geck's picture of the center of NGC 3597 is here.

Geck, your pictures are a lot paler, colorwise, than the ESA Hubble Picture of the Week, posted by bystander. Is there a reason for that? Maybe the new, colorful image has been constructed from images taken through more than two filters.


Ann

[geckzilla]

That one's not mine and "acknowledgement" has never meant that I did the processing on the pictures. It has always only meant that I helped dig it out of the archive. Mine only has two filters while ESA's artist has used a couple more. I don't remember why I did that.

[Glima49]

Ou4: A Giant Squid Nebula
http://www.astrobin.com/235869/
Copyright: Emmanuel Malakopoulos

Click to view full size image

[starsurfer]

LBN 310
http://www.alessandrofalesiedi.it/deep-sky/lbn-310/
Copyright: Alessandro Falesiedi

[starsurfer]

vdB140
http://www.astrobin.com/220917/F/
Copyright: Tero Turunen

[starsurfer]

LBN 258 and GM 2-41
http://www.myastroscience.com/#!cygnus-x-dr15/c1a02
Copyright: Sergio Kaminsky

Click to view full size image

LBN 258 is the emission nebula and GM 2-41 is the reflection nebula in the top left corner.