APOD: Arp 188 and the Tadpoles Tidal Tail (2010 Sep 26)

[APOD Robot]

Arp 188 and the Tadpoles Tidal Tail

Explanation: Why does this galaxy have such a long tail? In this stunning vista recorded with the Hubble Space Telescope's Advanced Camera for Surveys, distant galaxies form a dramatic backdrop for disrupted spiral galaxy Arp 188, the Tadpole Galaxy. The cosmic tadpole is a mere 420 million light-years distant toward the northern constellation Draco. Its eye-catching tail is about 280 thousand light-years long and features massive, bright blue star clusters. One story goes that a more compact intruder galaxy crossed in front of Arp 188 - from left to right in this view - and was slung around behind the Tadpole by their gravitational attraction. During the close encounter, tidal forces drew out the spiral galaxy's stars, gas, and dust forming the spectacular tail. The intruder galaxy itself, estimated to lie about 300 thousand light-years behind the Tadpole, can be seen through foreground spiral arms at the lower left. Following its terrestrial namesake, the Tadpole Galaxy will likely lose its tail as it grows older, the tail's star clusters forming smaller satellites of the large spiral galaxy.

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[ketarax]

It's a striking image. Any idea if the nebulosity that seems to be centered and normal to the galactic plane of the largest background galaxy is a jet of some sort, or another gravitational tail / stream ?

[Ann]

I've noticed that jet too. I believe it is a jet, but it could be a tidal tail too. Please note, however, that Arp 188 itself also seems to have a jet, which is extending "down" at a 90 degrees angle from the disk surrounding the nucleus of the galaxy. However, this jet(?) clearly doesn't originate from the nucleus of Arp 188.

Personally I wonder if the jet/tidal tail of the large white background galaxy is in any way connected to a smaller pair of interacting whitish galaxies to the lower left of the edge-on disk galaxy. The interacting pair is slightly yellower in color than the larger edge-on galaxy, but they might conceivably be at the same redshift, interacting with the edge-on galaxy. In that case the plume extending from the large white edge-on galaxy might be a combination of a jet and a tidal tail caught up in the gravitational field of the interacting pair.

All in all, this image contains a huge number of extremely fascinating background galaxies. Please take some time to examine them. If you wish to you can examine them here, where you can enlarge the image so much that you can really see the background galaxies:

http://www.spacetelescope.org/images/heic0206a/

Ann

[orin stepanek]

It looks like there is a faint trail from the Tadpole to the galaxy on the right.

[neufer]

I believe it is a jet, but it could be a tidal tail too.

Oh, Ann, Ann, Ann.

1) Jets shoot perpendicularly out of the center of galaxies not tangentially out of their arms
and they usually have counter jets shooting out the opposite direction.

2) Jets are made up of particles radiating strongly in radio in x-rays NOT of stars & dust.

3) "The intruder galaxy itself can be seen through foreground spiral arms at the lower left."

[mexhunter]

It is a beautiful image.
Geetings
César

[neufer]

[c]The Tadpole -OR- The Chainsaw ?[/c]
<<In 2001, Westerbork observations of the disturbed galaxy named VV-29 (alias Arp-188, UGC-10214) showed that there is second smaller galaxy (named VV-29c) that appears behind the western side of the main body of the distorted galaxy. Through its gravitational forces during a close orbital encounter, this second galaxy appears to have been responsible for raising the long `tail of the tadpole' that extends outward from VV-29. VV-29 received wide press coverage during May 2002, when it appeared on the front pages of major newspapers to announce the commissioning of the Hubble Space Telescope's Advanced Camera. The galaxy was featured as the May 2, 2002 Astronomy Picture of the Day. The bright, blue-ish center of the new galaxy VV-29c can be seen through the double spiral arms of VV-29.

Click to view full size image

The mosaic of images [right] compares the HST image with two other diagnostic images: one comes from the Westerbork Radio Synthesis Telescope, and the second from the 2.5m Isaac Newton optical telescope in La Palma. The images are oriented with north upward and east to the left. The color radio image records the emission from the galaxy in the 21cm line of neutral hydrogen, indicating both the extent of the hydrogen gas and its velocity along the line of sight to the observer (using the Doppler effect). The blue end of the spectrum indicates the regions in the galaxy that are approaching us, while the red regions of the `velocity field' indicate recession. The WSRT observations revealed the second galaxy VV29c through its velocity offset, which you can see as the [RECEDING] RED background object that is viewed through the artificial perforation in the velocity field on the right side of the galaxy. The very deep Isaac Newton Telescope image has also been heavily smoothed to bring out the faintest diffuse light levels. This reveals additional structures not seen in the HST image: a faint counter-arm to the right, and a vertical spur on the left side of the main body of the galaxy.
.........................................................
GALAXY NAMES: Galaxies acquire names when their coordinates in the sky are measured and they are listed in catalogs for subsequent study by astronomers. For example, the interesting system pictured above has a large number of `aliases', which result from its listing in several popular catalogs. The first catalog to list it was the Vorontsov-Velyaminov "Atlas and Catalog of Interacting Galaxies", published in 1959. This galaxy was the 29th object listed in the catalog. In fact, Vorontsov-Velyaminov actually split the galaxy into two parts: VV-29a, the main body of the galaxy, and VV-29b, the tidal tail that extends to the east (left) in the pictures. When the third galaxy was discovered in the WSRT data, the observing team (Briggs, Moller, Higdon, Trentham, Ramirez-Ruiz) decided to continue this convention by naming the new galaxy VV-29c. VV-29 has other names, which result from its appearance in many catalogs: Arp-188 (in Arp's "Atlas of Peculiar Galaxies," 1966), CGCG275-023 (in Zwicky's "Catalogue of Galaxies and of Clusters of Galaxies," 1966), UGC10214 (in Nilson's "Uppsala General Catalogue of Galaxies," 1973). When VV-29 had its 15 minutes of fame in May 2002, it appeared under the name "The Tadpole Galaxy," but based on the images above, we will always think of it as "The CHAINSAW"!

PUBLISHED PAPER: 2001, A&A, 380, 418 (Briggs, Moller, Higdon, Trentham, Ramirez-Ruiz). "Did VV 29 collide with a dark Dark-Matter halo?" >>

[Ann]

I believe it is a jet, but it could be a tidal tail too.

Oh, Ann, Ann, Ann.

1) Jets shoot perpendicularly out of the center of galaxies not tangentially out of their arms
and they usually have counter jets shooting out the opposite direction.

2) Jets are made up of particles radiating strongly in radio in x-rays NOT of stars & dust.

3) "The intruder galaxy itself can be seen through foreground spiral arms at the lower left."

So I was wrong. Sue me!

Click to play embedded YouTube video.

Except I'm a girl. And I'm not named Sue.

Ann

[ketarax]

I believe it is a jet, but it could be a tidal tail too.

Oh, Ann, Ann, Ann.

1) Jets shoot perpendicularly out of the center of galaxies not tangentially out of their arms
and they usually have counter jets shooting out the opposite direction.
3) "The intruder galaxy itself can be seen through foreground spiral arms at the lower left."

O neufer, I think you mistook which object we were speculating about. As the image appears on the APOD page, the is-it-a-jet -galaxy is about half the image width to the right from Tadpole.

2) Jets are made up of particles radiating strongly in radio in x-rays NOT of stars & dust.

This is certainly a valid point, however, it doesn't apply universally to everything we call jets, c.f. Messier 87.

[neufer]

So I was wrong. Sue me!

Except I'm a girl. And I'm not named Sue.
Ann

<<Sue Ann Nivens was a fictional character on the long-running TV situation comedy, The Mary Tyler Moore Show. She was played by television perennial Betty White. A forerunner of Martha Stewart, Sue Ann Nivens was the relentlessly perky star of "The Happy Homemaker", on Mary Richards' fictional WJM-TV, Minneapolis, Minnesota. Her show had unusual and sometimes ludicrous themes such as "What's all this fuss about famine?" and "A salute to fruit". Like Stewart, she was a perfectionist; she once confessed she would rather flush her Veal Prince Orloff down a toilet than serve it reheated. She was also consumed with helpful hints for all occasions and always ready to make lemons into lemonade; she once suggested buying colorful, happy goldfish as companions for the infirm and then, when the goldfish died, using them as fertilizer for houseplants.>>

[xanthoptica]

I have a background galaxy question for everyone. Personally, I get more entranced by all the background galaxies in images like this. In staring at them all, they seem to have a decidedly warm, reddish cast in general. Given that they are more distant objects, I wonder: are we actually seeing redshift in the visible spectrum of these distant objects? Anybody know?

[bystander]

2) Jets are made up of particles radiating strongly in radio in x-rays NOT of stars & dust.

This is certainly a valid point, however, it doesn't apply universally to everything we call jets, c.f. Messier 87.

Are you saying the M87 jet is not a particle stream?

http://asterisk.apod.com/vie ... 31&t=20688

[ketarax]

This is certainly a valid point, however, it doesn't apply universally to everything we call jets, c.f. Messier 87.

Are you saying the M87 jet is not a particle stream?

Well I guess I sort of am, but that's just sloppy expression from my part. The remark about Messier 87 was made to emphasize the fact that some jets are seen in visible light, as well. But I guess all of them are seen even better in X-rays/radio?

As for the speculative jet in today's APOD, I'm close to a personal conclusion that it is actually "stars and dust" as in a tidal tail, and not a jet output from a supermassive black hole.

[bystander]

http://en.wikipedia.org/wiki/Sue_Ann_Nivens

Although apparently charming and sweet, Sue Ann was really sardonic, and very, very competitive. Always with her trademarked dimpled smile, she was cruel and snide toward people she did not like or felt threatened by.

Maybe a little Sue Ann in you?

[ketarax]

Given that they are more distant objects, I wonder: are we actually seeing redshift in the visible spectrum of these distant objects? Anybody know?

I've seen that explanation in a caption once or many times, but I'm not qualified to confirm it's the correct one. Perhaps we're seeing the combined effect of redshift and stellar makeup of those early galaxies. In any case, I'm not aware of any relatively close galaxies that appear quite as red.

[Ann]

Given that they are more distant objects, I wonder: are we actually seeing redshift in the visible spectrum of these distant objects? Anybody know?

I've seen that explanation in a caption once or many times, but I'm not qualified to confirm it's the correct one. Perhaps we're seeing the combined effect of redshift and stellar makeup of those early galaxies. In any case, I'm not aware of any relatively close galaxies that appear quite as red.

Yes, the very reddest objects are all reddened by redshift. They are all very distant. But they can look even redder if they are elliptical galaxies made up entirely of yellow to yellow-orange stars.

At the upper left corner there is a group of very red galaxies. One of these galaxies is definitely an elliptical, and it is very red with a noticable red halo. Two galaxies appear to be flattened lenticulars, and one, the least red of the lot, may be a one-armed spiral, although it looks weird. Two appear to be irregulars, and one of them is definitely forming new stars.

Ann

[neufer]

http://en.wikipedia.org/wiki/Sue_Ann_Nivens

Although apparently charming and sweet, Sue Ann was really sardonic, and very, very competitive.

Always with her trademarked dimpled smile, she was cruel and snide toward people she did not like or felt threatened by.

Maybe a little Sue Ann in you?

Just how exactly do you know about my trademarked dimpled smile

[bystander]

Just how exactly do you know about my trademarked dimpled smile

[neufer]

Given that they are more distant objects, I wonder: are we actually seeing redshift in the visible spectrum of these distant objects? Anybody know?

I've seen that explanation in a caption once or many times, but I'm not qualified to confirm it's the correct one. Perhaps we're seeing the combined effect of redshift and stellar makeup of those early galaxies. In any case, I'm not aware of any relatively close galaxies that appear quite as red.

Yes, the very reddest objects are all reddened by redshift.

Around the Ragnarök the rugged rascal ran.

Redshift mostly but interstellar medium (ISM) extinction might also play a factor:

Average extinction curves for the MW, LMC2, LMC, & SMC Bar. The curves are plotted versus 1/wavelength to emphasize the UV.

---

[Ann]

It's a striking image. Any idea if the nebulosity that seems to be centered and normal to the galactic plane of the largest background galaxy is a jet of some sort, or another gravitational tail / stream ?

Ketarax, as for your original quesiton, it could be a star stream. See this image of NGC 4651 for comparison, plus the accompanying APOD caption:

http://apod.nasa.gov/apod/ap100415.html

Ann

[neufer]

Ketarax, it could be a star stream.
See this image of NGC 4651 for comparison

Star streams are themselves extensive trails of stars stripped from smaller satellite galaxies.

[Qev]

That 'jet' from the background spiral galaxy, on a closer look, actually appears to be originating from the bright compact object just 'below' the spiral galaxy.

[wagoneer4x4]

i wish apod would stop using the term "mere" in almost every reference to large astronomical distances. it stopped being amusing awhile back.

[neufer]

i wish apod would stop using the term "mere" in almost every reference to large astronomical distances.
it stopped being amusing awhile back.

I sort of agree with "wagoneer4x4" here.

The phrase "A MERE 'N' light-years away" should probably be limited to discussing:

• 1) close foreground objects (versus more distant background objects)
  
  or 2) the nearest of neighboring stars, pulsars, galaxies, clusters of galaxies, etc..

If indeed:

• 1) the cosmic tadpole {A MERE 420 million light-years distant (2010 September 26)}
  
  or 2) the "bullet cluster" {A MERE 3.4 billion light-years away (2008 August 23)}

are, in fact, the closest examples of their kind then it should be explicitly stated as such.

Otherwise one can only assume that the APOD is simply being facetious (; perish the thought ).

• And it's old and old it's sad and old it's sad and weary I go back to you, my cold father, my cold mad father, my cold mad feary father, till the near sight of the MERE size of him, the moyles and moyles of it, moananoaning, makes me seasilt saltsick...
  - Finnegans Wake (last page)

[Stevie]

All the discussion here seem to be missing somthing I'm seeing in the image. That small galaxy jsut behind the Tadpole, with it's jet comming out of the centre doesn't look right. Jet's coming out of black hole normally go straight, at least thats how they appear in most other photo's.

Yet this Jet seems to go straight, then suddenly at the end bends in one direction? Huh? I thought they aren't meant to do that? What's making the bend? It looks like a wind of some sort is blowing it, sure I know there is no wind in space, but that's just how it looks to me at least.

Doesn't anyone else find something odd about it? This jet goes straight for a while then bends and fades out... Very strange. Not like the rest, some other do spread out thought, yet this jet isn't doing that either.

p.s. The 1st question I was asked to post this said what "Name" is the natural satellite orbiting earth. I said "Lunar" ...which I thought is the correct name for the moon... grrr I thought it was a trick question... So our moon is called moon?? It's like calling a pet Dog "Dog" or giving your new child the name "Human". ...doesn't make a lot of sense does it?