UV Andromeda (2009 Sept 17)

Star*Hopper · Post by **Star*Hopper** » Thu Sep 17, 2009 2:29 pm

http://apod.nasa.gov/apod/ap090917.html

Now THERE's you an APOD-worthy astrophoto!
The visual spectrum overlay adds a super touch - kudos & great job on the selection.
This one - if not my favorite it's right up in there with the best of 'em!

THANX!

neufer · Post by **neufer** » Thu Sep 17, 2009 3:22 pm

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The Andromeda Galaxy pictured in ultraviolet light by Swift
The Andromeda Galaxy pictured in ultraviolet light by GALEX

The Andromeda Galaxy taken by Spitzer in infrared, 24 micrometres
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http://www.nasa.gov/mission_pages/swift/bursts/uv_andromeda.html wrote:
<<In a break from its usual task of searching for distant cosmic explosions, NASA's Swift satellite has acquired the highest-resolution view of a neighboring spiral galaxy ever attained in the ultraviolet. The galaxy, known as M31 in the constellation Andromeda, is the largest and closest spiral galaxy to our own.

"Swift reveals about 20,000 ultraviolet sources in M31, especially hot, young stars and dense star clusters," said Stefan Immler, a research scientist on the Swift team at NASA's Goddard Space Flight Center in Greenbelt, Md. "Of particular importance is that we have covered the galaxy in three ultraviolet filters. That will let us study M31's star-formation processes in much greater detail than previously possible."

Between May 25 and July 26, 2008, Swift's Ultraviolet/Optical Telescope (UVOT) acquired 330 images of M31 at wavelengths of 192.8, 224.6, and 260 nanometers. The images represent a total exposure time of 24 hours. The task of assembling the resulting 85 gigabytes of images fell to Erin Grand, an undergraduate student at the University of Maryland at College Park who worked with Immler as an intern this summer. "After ten weeks of processing that immense amount of data, I'm extremely proud of this new view of M31," she said.

Several features are immediately apparent in the new mosaic. The first is the striking difference between the galaxy's central bulge and its spiral arms. "The bulge is smoother and redder because it's full of older and cooler stars," Immler explained. "Very few new stars form here because most of the materials needed to make them have been depleted."

Dense clusters of hot, young, blue stars sparkle beyond the central bulge. As in our own galaxy, M31's disk and spiral arms contain most of the gas and dust needed to produce new generations of stars. Star clusters are especially plentiful in an enormous ring about 150,000 light-years across.

I fell into a burning ring of fire
I went down, down, down and the flames went higher
And it burns, burns, burns, the ring of fire
The ring of fire
What triggers the unusually intense star formation in Andromeda's "ring of fire"? Previous studies have shown that tides raised by the many small satellite galaxies in orbit around M31 help boost the interactions within gas clouds that result in new stars.

In 1885, an exploding star in M31's central bulge became bright enough to see with the naked eye. This was the first supernova ever recorded in any galaxy beyond our own Milky Way. "We expect an average of about one supernova per century in galaxies like M31," Immler said. "Perhaps we won't have to wait too long for another one."

"Swift is surveying nearby galaxies like M31 so astronomers can better understand star- formation conditions and relate them to conditions in the distant galaxies where we see gamma-ray bursts occurring," said Neil Gehrels, the mission's principal investigator at NASA Goddard. Since Swift's November 2005 launch, the satellite has detected more than 400 gamma-ray bursts -- massive, far-off explosions likely associated with the births of black holes.>>

bystander · Post by **bystander** » Thu Sep 17, 2009 4:57 pm

Swift Makes Best-ever Ultraviolet Portrait of Andromeda Galaxy

neufer wrote:The Andromeda Galaxy pictured in ultraviolet light by GALEX

NASA/JPL-Caltech/GALEX (top), REU program/NOAO/AURA/NSF (bottom)

neufer wrote:The Andromeda Galaxy taken by Spitzer in infrared, 24 micrometres

NASA/JPL-Caltech/Spitzer (IR), NOAO/AURA/NSF (visible)

bystander · Post by **bystander** » Thu Sep 17, 2009 6:25 pm

The Andromeda Galaxy pictured in x-rays by Chandra

Chandra X-ray Image of Andromeda Galaxy (M31)

This color-coded Chandra image (Red: 0.5-1.0 keV; Green: 1.0-2.0 keV; Blue: 2.0-4.0 keV) shows the central region of the Andromeda Galaxy, a.k.a. M31 where a diffuse, X-ray emitting cloud of hot gas was discovered in the midst of a collection of point-like sources.

(Credit: NASA/UMass/Chandra)

NOAO Optical & Chandra X-ray Image of Andromeda Galaxy (M31)

The optical image of the Andromeda Galaxy (M31) was taken at the NSF's 0.9-meter telescope on Kitt Peak with the NOAO Mosaic CCD camera.

(Credit: Optical: NOAO/AURA/NSF/Kitt Peak; X-ray: NASA/UMass/Chandra)

Chandra X-ray & Spitzer Infrared Image of Andromeda Galaxy (M31)

In this Chandra/Spitzer composite, red represents Spitzer's 24 micron mid-infrared data, green represents low-energy X-rays from Chandra (0.5-2.0 keV), and blue represents high-energy X-rays from Chandra (2.0-4.0 keV).

(Credit: X-ray: NASA/UMass/Chandra; Infrared: NASA/JPL-Caltech/Spitzer)

http://chandra.harvard.edu/photo/2006/m31/more.html

neufer · Post by **neufer** » Thu Sep 17, 2009 7:37 pm

http://chandra.harvard.edu/photo/2001/0007rev/ wrote:
<<Chandra and Hubble Space Telescope images of two recently detected emitting globular star clusters - so called because of their spherical shape - were used as a cross-check to determine the position of X-ray sources near the center of the Andromeda galaxy to an accuracy ten times greater than before. The inset shows the three Chandra sources closest to the supermassive black hole, overlaid with the intensity contours from the HST image (red). The location of supermassive black hole is thought to be in the middle of the peanut-shaped intensity contours, and very close to the Northern-most of the three Chandra sources.

These highly accurate positions show that the very cool X-ray source (blue) previously identified with the supermassive black hole in the center of the galaxy is actually about 10 light years south of the center. A second, hotter X-ray source, is found to be at a position consistent with the position of the super massive black hole. The globular clusters are outside the field of view in this image.>>

Gecko23 · Post by **Gecko23** » Thu Sep 17, 2009 11:53 pm

I really liked this one. Andromeda is an absolutely beautiful galaxy, and it was nice to be able to compare it in visible and ultraviolet. You can see so many details in UV!

Here's something that I found on the UV image that didn't appear in the visible. The image I cropped below includes the bright star at the lower right of the image. What could these three circles be?

neufer · Post by **neufer** » Fri Sep 18, 2009 2:19 am

Gecko23 wrote:Here's something that I found on the UV image that didn't appear in the visible.
The image I cropped below includes the bright star at the lower right of the image.

What could these three circles be?

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http://en.wikipedia.org/wiki/Borromean_rings wrote:
In mathematics, the Borromean rings consist of three topological circles which are linked
and form a Brunnian link, i.e., removing any ring results in two unlinked rings.

The name "Borromean rings" comes from their use in the coat of arms of the aristocratic Borromeo family in Italy.
The link itself is much older and has appeared in Ghandarva (Afghan) Buddhist art from around the second century C.E.,
and in the form of the valknut on Norse image stones dating back to the 7th century.

The Borromean rings have been used in different contexts to indicate strength in unity, e.g. in religion or art. In particular, some have used the design to symbolize the Trinity. The psychoanalyst Jacques Lacan famously found inspiration in the Borromean rings as a model for his topology of human subjectivity, with each ring representing a fundamental Lacanian component of reality (the "real", the "imaginary", and the "symbolic"). The Borromean rings were also the logo of Ballantine beer.>>

geckzilla · Post by **geckzilla** » Fri Sep 18, 2009 2:46 am

It is a weird lens flare from one of those pesky foreground stars... or it could be where the aliens get their crop circle ideas from.

Art, are you good at trivial pursuit?

neufer · Post by **neufer** » Fri Sep 18, 2009 3:54 am

geckzilla wrote:It is a weird lens flare from one of those pesky foreground stars...
or it could be where the aliens get their crop circle ideas from.

Art, are you good at trivial pursuit?

Sometimes.
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http://en.wikipedia.org/wiki/Pursuit_curve wrote:
<<A curve of pursuit is a curve constructed by analogy to having a point or points which represents pursuers and pursuees, and the curve of pursuit is the curve traced by the pursuers.>>

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http://en.wikipedia.org/wiki/Tractrix wrote:
<<Tractrix (from the Latin verb trahere "pull, drag") is the curve along which a small object moves, under the influence of friction, when pulled on a horizontal plane by a piece of thread and a puller that moves at a right angle to the initial line between the object and the puller at an infinitesimal speed. It is therefore a curve of pursuit.

The tractrix was first introduced by Claude Perrault (brother to Charles Perrault the teller of fairy tales) in 1670, and later studied by Sir Isaac Newton (1676) and Christian Huygens (1692).>>

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http://en.wikipedia.org/wiki/Logarithmic_spiral wrote:
___ Logarithmic spirals in nature

* The approach of a hawk to its prey. Their sharpest view is at an angle to their direction of flight; this angle is the same as the spiral's pitch.

* The approach of an insect to a light source. They are used to having the light source at a constant angle to their flight path. Usually the sun (or moon for nocturnal species) is the only light source and flying that way will result in a practically straight line.

* Many biological structures including the shells of mollusks.

* The arms of spiral galaxies. Our own galaxy, the Milky Way, is believed to have four major spiral arms, each of which is roughly a logarithmic spiral with pitch of about 12 degrees, an unusually small pitch angle for a galaxy such as the Milky Way. In general, arms in spiral galaxies have pitch angles ranging from about 10 to 40 degrees.

* The arms of tropical cyclones, such as hurricanes.

* The nerves of the cornea.>>

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Star*Hopper · Post by **Star*Hopper** » Fri Sep 18, 2009 11:07 am

Gecko23 wrote:I really liked this one. Andromeda is an absolutely beautiful galaxy, and it was nice to be able to compare it in visible and ultraviolet. You can see so many details in UV!

Here's something that I found on the UV image that didn't appear in the visible. The image I cropped below includes the bright star at the lower right of the image. What could these three circles be?

^^^^^^^^

My first inclination was to think them photographic artifacts, eg lens flares.

I too had noticed that region, actually, while wondering about something else -- what appears to be flare around the brighter object nearby is unsettlingly off-center of what one might expect. After your post, I decided to take a closer look.

First, in SkyTools I identified the bright central object as star HD 3914 / HIP 3293. After taking an angular measure to the nearest stars to it for alignment & ID purposes, I pulled up a 4' plot around HD 3914 in SIMBAD.

After orienting my chart with the APOD images via those 4 very faint stars in the region (roughly) SW of HD 3914, I determined they were (from north-to-south) Pul -3 50211, & 2MASS #s J00421007+4040086, J00420301+4039430, & J00420303+4038418. Pulling up a 4' plot in SIMBAD, the only thing between those 4 stars & HD 3914 - the position of your 3 'circles' - was a single object: Bol 65, a Globular Cluster, at coords 00 42 01.91 +40 40 13.0 [J2K].

A single object : 3 'circles'. Hmmmm. Unless SIMBAD's plot doesn't include all actual objects in that area, intriguing indeed.

Anybody got anything more conclusive?

+++
The whole UV Andromeda is astonishing in what it reveals. I have literally sat here for hours 'flipping' back & forth between the two images. So MANY items of interest, especially in seeing how objects so very bright in the visible spectrum seem to almost disappear in UV, & vice versa - as well as how bright they are in UV while so exceedingly dim & barely detectable in visible light. And also vice versa! You might expect most of the brighter objects to proportionatly emit more UV light - same in either spectrum for that matter, but that's clearly not the case as a trend.

Another thing I find fascinating is how much structure shows up in UV that appears almost completely absent in visible. One would expect a far more even disbursement of UV sources - plenty of them, sure, but more evenly spread, randomly across the image. Making me wonder, why so much 'clumping' of UV sources? What makes one particular region so conducive to 'hosting' a heavy majority of UV emitting objects, than another? Or more basically, what 'put' them there, to start with? I can't see it as being just chance alignment.

Truly wondering,
~S*H

JohnD · Post by **JohnD** » Fri Sep 18, 2009 12:03 pm

"Logarithmic Spirals in nature - the nerves of the cornea of the eye"

See: http://www.iovs.org/cgi/content/full/48/4/1535/F4

I didn't believe it until I saw it!

John

neufer · Post by **neufer** » Fri Sep 18, 2009 12:49 pm

geckzilla wrote:It is a weird lens flare from one of those pesky foreground stars...
or it could be where the aliens get their crop circle ideas from.

Aliens? What aliens? _______ [H1N1]

Gecko23 · Post by **Gecko23** » Sun Sep 20, 2009 2:42 am

If it's a lens flare, can anyone provide an explanation for why the lens flare takes this strange shape, or at least provide any examples of similar lens flares?

geckzilla · Post by **geckzilla** » Sun Sep 20, 2009 4:16 am

I had an idea that there are three circles to the lens flare because it's actually three lens flares. You can kind of see that dim, faint, purplish hue circle looks like it was repeated 3 times too. And you can see how the stars from at least three exposures didn't quite line up either. So each time the exposure was taken, the lens flare shifted position a little. One thing I can't explain is why the star apparently has a black dot in front of it. Maybe they were trying to block out the light of the star since they knew it would drown the surroundings out but the dot wasn't quite big enough? Sorry I don't have any kind of definitive answer but it might help you formulate your own ideas too.

Star*Hopper · Post by **Star*Hopper** » Sun Sep 20, 2009 1:47 pm

I'm now leaning strongly towards lens flare or other photographic artifact.

I blew up that segment several x to study the overlap areas of the tori, and discovered another, though very faint, which I circled in red in this screencap:

Oddly, it doesn't show very well or at all in 2 other monitors where I viewed it, so you might have difficulty - try viewing at different angles, or kick up brightness.

At first I questioned why the artifacts appear here, & not around other bright sources....then I remembered this was but one image of a mosaic composite. Close examination will, however, reveal several others - hence my conclusion they are merely artifacts.

AFA the dark dot in center, a learned imager I know & respect has stated elsewhere on this board that those are in fact artifacts of the post-photographic processing.

What I don't understand is why 3, obviously brighter, in an area where only one exceedingly faint object (the globular I found in SIMBAD & mentioned previously) resides. Hence my short conclusion they're likely flares.

I can wonder - but I sure ain't gonna let it bother me!

~*

Chris Peterson · Post by **Chris Peterson** » Sun Sep 20, 2009 3:02 pm

Star*Hopper wrote:AFA the dark dot in center, a learned imager I know & respect has stated elsewhere on this board that those are in fact artifacts of the post-photographic processing.

What I don't understand is why 3, obviously brighter, in an area where only one exceedingly faint object (the globular I found in SIMBAD & mentioned previously) resides. Hence my short conclusion they're likely flares.

I wouldn't call them lens flares, since the imaging optics doesn't contain any lenses. It does contain some transmissive optics that might generate reflections, as well as internal structures that might reflect (although it is clear that a good deal of effort went into minimizing such reflections). In any case, "internal reflections" would probably be a better term if that's what is causing these artifacts. The donut shape is to be expected; the telescope is a Ritchey-Chretien design, so it has a circular central obstruction. Any out of focus stars (which is what you get with an internal reflection) will look like a shadow of that obstructed aperture. In addition, dust shadows that are not fully calibrated out will show up as donut shaped dark areas. Reflections off of different surfaces will produce different sized donut artifacts- something which is also seen in this image.

While there may be some processing artifacts, these bright spots are probably true optical artifacts. Similar artifacts are seen in most astronomical images because of the huge dynamic range of CCD cameras. If even a fraction of a percent of the energy from a bright source is misdirected by some sort of internal reflection, it will still be well above the camera's lower threshold of sensitivity.

Star*Hopper · Post by **Star*Hopper** » Sun Sep 20, 2009 3:22 pm

Yeah - I meant to say 'optical flares' -- total brainfart.
~*

geckzilla · Post by **geckzilla** » Sun Sep 20, 2009 10:57 pm

Oh, I guess I have been calling all internal reflections and flares as being part of the lens flare. I don't think I've ever seen a flare without an internal reflection unless the flare was so blown out you couldn't really see anything else. Most people don't have a need to distinguish the two.

neufer · Post by **neufer** » Mon Sep 21, 2009 8:42 am

Andromeda Galaxy in UV (Galex)

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I now know why those distant galaxies in Gravitational Lens photos
so often appear as "ghostly blue skeletons".....

http://antwrp.gsfc.nasa.gov/apod/ap090823.html
http://antwrp.gsfc.nasa.gov/apod/ap040807.html
http://antwrp.gsfc.nasa.gov/apod/ap070516.html
http://antwrp.gsfc.nasa.gov/apod/ap080728.html

They are redshifted UV images of spiral arms!

Chris Peterson · Post by **Chris Peterson** » Mon Sep 21, 2009 2:17 pm

neufer wrote:I now know why those distant galaxies in Gravitational Lens photos
so often appear as "ghostly blue skeletons".....

They are redshifted UV images of spiral arms!

That may be partly true, but I think it overlooks a lot of things. The apparent color depends on how the image was rendered (what filtered data is assigned to red, green, or blue), and it is different with different images- including those you linked. The UV Andromeda image is made through fairly narrowband filters, so other wavelengths (which would also be redshifted) are excluded. At the redshifts for most lensed galaxies, shifting to blue requires the source be around 100nm, which is quite a bit shorter than the UV Andromeda image range, so it's hard to compare them.

I think what you describe as a skeletal appearance has more to do with the fact that these distant galaxies are so dim that only the most active regions are visible once the image black point is set above the noise floor, and also to the distortion intrinsic to gravitational lensing.

Gecko23 · Post by **Gecko23** » Fri Sep 25, 2009 10:42 pm

Thanks for the great answer, Chris!

bystander · Post by **bystander** » Tue Oct 06, 2009 12:45 pm

HEAPOW: Andromeda Unchained (2009 October 05)

Star*Hopper · Post by **Star*Hopper** » Tue Oct 06, 2009 1:20 pm

Ya....but without the visible-band overlay.
APOD, FTW!
~;)

~S*H

neufer · Post by **neufer** » Tue Oct 06, 2009 1:21 pm

bystander wrote:HEAPOW: 2009 October 05 - Andromeda Unchained

http://en.wikipedia.org/wiki/Unchained_(film) wrote:
<<_Unchained_ is a 1955 prison film most remembered for its theme song, which became known as "Unchained Melody". The film was based on the career of Kenyon J. Scudder, former supervisor at Chino, as detailed in Scudder's book. Most of the scenes were actually filmed on location at the prison. Former football player Elroy "Crazylegs" Hirsch played the lead character, while other inmates were played by Chester Morris and Jerry Paris (later of The Dick Van Dyke Show), among others. Others in the cast included Peggy Knudsen and Barbara Hale, who appeared as women visiting the prisoners. You can lock them in "The Hole"...put them on bread and water...use the bull-whip and the black-jack...but they're still men...with a man's longings!>>

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http://www.imdb.com/title/tt0052782/ wrote:
_Hercules Unchained_ (1959)

With Steve Reeves as Hercules & Primo Carnera as Anteo, the giant

<<In route to Thebes for an important diplomatic mission, Hercules drinks from a magic spring and loses his memory. He spends most of the movie in the pleasure gardens of Queen Omphale of Lydia. While young Ulysses tries to help him regain his memory, political tensions escalate in Thebes, and Hercules' new wife Iole finds herself in mortal danger.>>

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http://mst3k.wikia.com/wiki/Hercules_Unchained wrote:
<<The musclebound Greek hero must summon all his strength to save the city of Thebes - and to save himself from the lusty queen of Lydia (Lopez), who finds herself very attracted to his male pulchritude.
.............................................................................
Segment One: Down in Deep 13 Frank and Dr. F's invention of decorator cockroaches gets an unintended boost from the star of today's movie Steve Reeves, where as Joel's invention of the Steve-O-meter runs into problems due to the prolific mind of Steve Allen.

Segment Two: Gypsy constructs a set to allow her to show her to be the Hellenistic ideal, but her ability in playing a harp brings this into question.

Segment Three: After partaking of the Water of Forgetfulness, Joel & the Bots try other foodstuffs and drinks which trigger other mental and emotional states: the Carrot Shake of Pretentiousness, the Blizzard of Loneliness, the Fruit-Striped Gum of Stability, and the Green Bean & French Onion Casserole of Happiness.

Segment Four: Tom and Crow try to get Joel to explain what Hercules and Queen Omphale are doing all day when they're cuddling and kissing, but he refuses to bite. Stinger: When Queen Omphale remembers the good times with Hercules, her eyes get real big.>>

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bystander · Post by **bystander** » Tue Oct 06, 2009 2:19 pm

Wikipedia wrote:In Greek mythology, Andromeda was the daughter of Cepheus and Cassiopeia, king and queen of the kingdom Ethiopia.

Her mother Cassiopeia bragged that she was more beautiful than the Nereids, the nymph-daughters of the sea god Nereus and often seen accompanying Poseidon. To punish the Queen for her arrogance, Poseidon, brother to Zeus and God of the Sea, sent the sea monster Cetus to ravage the coast of Ethiopia including the kingdom of the vain Queen. The desperate King consulted the Oracle of Zeus, who announced that no respite would be found until the king sacrificed his virgin daughter Andromeda to the monster. She was chained naked to a rock on the coast of Jaffa.

Perseus, returning from having slain the Gorgon Medusa, found Andromeda and slew Cetus. He set her free, and married her in spite of Andromeda having been previously promised to her uncle Phineus. At the wedding a quarrel took place between the rivals, and Phineus was turned to stone by the sight of the Gorgon's head (Ovid, Metamorphoses v. 1).

Andromeda followed her husband to Tiryns in Argos, and together they became the ancestors of the family of the Perseidae through the line of their son Perses. Perseus and Andromeda had seven sons: Perseides, Perses, Alcaeus, Heleus, Mestor, Sthenelus, and Electryon, and one daughter, Gorgophone. Their descendants ruled Mycenae from Electryon down to Eurystheus, after whom Atreus attained the kingdom, and would also include the great hero Heracles. According to this mythology, Perses is the ancestor of the Persians.

After her death, Andromeda was placed by Athena amongst the constellations in the northern sky, near Perseus and Cassiopeia. Sophocles and Euripides (and in more modern times Corneille) made the story the subject of tragedies.

So we have Andromeda unchained to thank for Iran.

YouTube: Anubis Gate - Andromeda Unchained

Starship Asterisk*