Milky Way Galaxy Cannibalizes Sagittarius

Reuters ^ | Wed Sep 24, 2003 4:11 PM ET

[anymouse]

Our Milky Way galaxy is gobbling up its galactic neighbor, Sagittarius, and on Wednesday, scientists offered documentary proof of this continuing cosmic cannibalism.

Astronomers have mapped the Sagittarius galaxy to show in detail how its debris wrap around and pass through the Milky Way, which contains Earth.

On its way to oblivion, the dwarf Sagittarius -- which is about 10,000 times the mass of the Milky Way -- is getting stretched, torn apart and ultimately eaten, scientists at the University of Virginia and the University of Massachusetts reported.

"It's clear who's the bully in the interaction," Steven Majewski of the University of Virginia, lead author of the report, said in a statement.

The study will be published in the Dec. 20 issue of the Astrophysical Journal.

The act of cannibalism had been obscured by stars and cosmic dust, but was revealed when astronomers looked for infrared radiation coming from stars known as M giants, which are common in Sagittarius but rare in the outer reaches of the Milky Way.

By focusing on these stars, the scientists said they were able to capture the totality of the Milky Way's meal, in a vision that makes it appear that our galaxy is slurping the stars of Sagittarius as if they were a stellar strand of spaghetti.

Before this work, astronomers had detected only a few scattered pieces of the disrupted Sagittarius dwarf. Even the existence of Sagittarius was unknown until the heart of our nearest satellite galaxy was discovered in 1994.

[anymouse]

The ultimate in white male Western hegemony. Clearly this abuse of our neighbors cannot be allowed to continue. Send in the United Nations peace keepers, right now! /sarcasm

[anymouse]

Space ping.

[Snuffington]

.... Minorities, women, and children to be hit hardest.

[GhostofWCooper]

"which is about 10,000 times the mass of the Milky Way"

This is an obvious typo. It must be 1/10,000th the mass, or else it would be eating us.

[4mycountry]

It's Bush's fault!!! </sarcasm>

[Calpernia]

ping

[Licensed-To-Carry]

Does PETA know about this?

[Aggie Mama]

Can someone please explain to me how in the world we can take pictures of our galaxy with us in it and know that we are a part of it?

[jammer]

I agreed with you until I went to the original post and looked at the pic. Not sure now.

[Concentrate]

What's-his-face was deeply saddened.

[TruthShallSetYouFree]

Our Milky Way galaxy is gobbling up its galactic neighbor,

Turn-about is fair play. I have a galactic neighbor who is up to 450 lbs from gobbling Milky Ways.

[I'm ALL Right!]

ping

[Lion in Winter]

Does that mean that everybody born under the sign of the Sagittarius will "disappear".... Or be gobbled up by a giant milky way bar?

( 8 > 0>

[Servant of the 9]

the dwarf Sagittarius -- which is about 10,000 times the mass of the Milky Way

Should be 1/10,000th

SO9

[TruthShallSetYouFree]

I don't know. But Almond Joying this thread immensely. It is Mounds of fun.

[jammer]

That's the new Mobile Fox MiniCam, launched by the Chinese several years ago. The pics are beamed back from the camera in Andromeda.

[jammer]

That's the new Mobile Fox MiniCam, launched by the Chinese several years ago. The pics are beamed back from the camera in Andromeda.

[Flying Circus]

I caught that one too. Doesn't Rueter have any editors to catch this stuff??

[jammer]

Sorry for the double--duplicitous?--post.

[Lion in Winter]

I snickered when I read your post! hahaha

[vger]

There's a mirror hanging on Andromeda!

[Rudder]

No typo, it is about 10,000 times the mass of the Milky Way. It's like the mouse eating the boa constrictor, our tiny Milky Way is nibbling away at the huge, but diffuse, Sagittarius galaxy.

[SwinneySwitch]

This IS hugh!

[Melas]

Too bad you caught it, because it's not a typo. Sagitarius is massive, incredibly massive. But....the Milky Way is dense, incredibly dense. The photo that accompanies the story does a good job of showing the huge but diffuse galazy almost surrounded the incredibly bright but tiny milky way.

[KayEyeDoubleDee]

Almond Joying this thread immensely.

Thanks for the laugh. Possibly my first of the day...

[William Tell]

Aggie Mama said: "Can someone please explain to me how in the world we can take pictures of our galaxy with us in it and know that we are a part of it?"

Imagine that you are located somewhere in an immense flat desert.

You point a telescope at a distant green dot. The telescope reveals that the distant dot is, in fact, a grouping of individual palm trees.

Pointing the telescope at other green dots reveals that the desert seems to be populated with these groupings of trees. The closest of these groupings are several miles away. Some of them are hundreds of miles away.

When you put down the telescope, you notice that you are somewhere in the middle of a grouping of trees. Of the trees that you can see without a telescope, the one farthest away is only 100 yards away. All other known trees are either closer than 100 yards or they are located in groupings that are only visible in the telescope and at least several miles away.

All of the evidence is consistent with the assumption that you are located in a grouping of trees which, if viewed from one of the distant green dots, would itself be just a distant green dot.

[Bogey78O]

We're not taking it head on. It's more of a defection.

[LiteKeeper]

SPOTREP

[AndrewC]

BUUUURRRRPP!

[Centurion2000]

"It's clear who's the bully in the interaction," Steven Majewski of the University of Virginia, lead author of the report, said in a statement.

Ok, NEVER trust anything that a scientist says if they are directly give anthropomorphic attributes to inanimate objects they are studying.

[Unknowing]

Please forgive my ignorance, Melas, but perhaps you might explain what seems to be a physically counterintuitive conclusion in the article. If Sagittarius is a "dwarf," then why does it appear so large in the illustration? And if the dwarf Sagittarius is both smaller and less dense than the Milky Way, how can it contain so much more mass than the larger and denser Milky Way?

[FormerlyAnotherLurker]

It is a "dwarf galaxy" - hence, it is a typo. There is no way it is 10,000X the mass of the Milky Way.

" Abstract
We have discovered a new Galactic satellite galaxy in the constellation of Sagittarius. The Sagittarius dwarf galaxy subtends an angle of ~10 deg on the sky, lies at a distance of 24 kpc and is comparable in size and luminosity to the largest dwarf spheroidal, Fornax. The new galaxy has many features in common with the other eight Galactic dwarf spheroidal systems, including an extended low-density spatial structure, a well-populated red horizontal branch with a blue extension, and a substantial carbon star population. In terms of stellar populations it most closely resembles the Fornax dwarf, having a strong intermediate-age stellar component and evidence of a metallicity spread. Sagittarius is the nearest galaxy known and currently lies only ~16 kpc from the centre of the Milky Way. Isodensity maps show it to be markedly elongated along a direction pointing towards the Galactic Centre, and suggest that it has been tidally distorted. The close proximity to the Galactic Centre, the morphological appearance and the radial velocity of 140 km s^-1 indicate that this system must have undergone at most very few close orbital encounters with the Milky Way. It is currently undergoing strong tidal disruption prior to being integrated into the Galaxy. We find that at least some of the four globular clusters, M54, Arp 2, Ter 7 and Ter 8, are associated with the Sagittarius dwarf galaxy, and will probably share the fate of their progenitor. The Sagittarius dwarf galaxy was found serendipitously using a combination of UK Schmidt Telescope sky survey plates, the APM automatic plate measuring facility and the Anglo-Australian Telescope multifibre spectrograph, AUTOFIB."

FROM:

http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995MNRAS%2E277%2E%2E781I&db_key=AST

[Rudder]

Our Milky Way galaxy (center/blue) is gobbling up its galactic neighbor, Sagittarius, (red trail, from left to right) and on September 24, 2003, scientists offered documentary proof of this continuing cosmic cannibalism. On its way to oblivion, the dwarf Sagittarius -- which is about 10,000 times the mass of the Milky Way -- is getting stretched, torn apart and ultimately eaten, scientists at the University of Virginia and the University of Massachusetts reported. REUTERS/Handout

I see, it just looks bigger than the Milky Way in these pictures, right?

[mtbopfuyn]

It's a vast right-winged conspriacy.

[Blue Scourge]

lol...I was thinking the same thing...better call the ACLU and Greenpeace.

[FormerlyAnotherLurker]

Sarcasm? Don't know what the pictures are since I don't waste connect time with pictures.

You might try looking up the definitions of dwarf galaxy, extended low-density spatial structure, tidally distorted, etc.
The author of the news piece is an idiot or a bad typist.

BUT:
"Known as the Sagittarius dwarf spheroidal galaxy -- since it is observed in the direction of the constellation Sagittarius -- it is roughly one-tenth the diameter of the Milky Way but weighs less than one-thousandth as much as the Milky Way. It is nearly as close to the center of our own galaxy as is the Earth. The galaxy is one of nine known nearby, or companion, dwarf spheroidal galaxies to the Milky Way."

FROM:
http://www.jhu.edu/news_info/news/home98/feb98/invader.html Office of News and Information - Johns Hopkins University

[FormerlyAnotherLurker]

#36 looks real sarcastic in print - sorry. BUT the original post is dead wrong. Maybe at work Monday I'll look at the picture, as for now I'm many miles away from a high speed connection.

[Rudder]

"Dwarf" means nothing without a referent. I mean, a pigmy human being is bigger than a giant pansy. I was going by the text and the picture together. The picture must be misleading but it does corroborate the text, which must be misleading (but it corroborates the picture.) If you're correct (and I am not saying you are not) then this article is far more screwed up than a mere typographical error.

[natewill]

I don't know. But Almond Joying this thread immensely. It is Mounds of fun.

(Snicker snicker)

[FormerlyAnotherLurker]

"If you're correct" ? I'm hurt. LOL

I bit the bullet and went to Steve's homepage (met him at UofChicago, a long time ago, in a galax...

FROM:
http://www.astro.virginia.edu/~mfs4n/sgr/
" The study, to be published in the Dec. 20 issue of the Astrophysical Journal, is the first to map the full extent of the Sagittarius galaxy and show in visually vivid detail how its debris wraps around and passes through our Milky Way. Sagittarius is 10,000 times smaller in mass than the Milky Way, so it is getting stretched out, torn apart and gobbled up by the bigger Milky Way."

I NEVER trust reporters - print or web - they seem to have a translation mechanism that's faulty for things they don't understand.

There appear to be several pictures there but I'm getting old and can't wait for dial-up over an archaic phone system.

[kstewskis]

I don't know. But Almond Joying this thread immensely. It is Mounds of fun.

(Snicker snicker)

I wonder when it will devour Mars? Next Pay Day?

[Squantos]

Duct tape.............lots of duct tape is how !

Just how I'd do it. Stay Safe !

[mhking]

There's where those pesky Xindi are coming from...

Just damn.

If you want on the new list, FReepmail me. This IS a high-volume PING list...

[As i mentioned, the B/C & JD! lists are going to float into and out of whack over the forseeable future, while I try to cobble a rig back together for myself. My apologies for any incovenience or misunderstandings in this time frame. New signups/removals may be flaky in this time-frame as well; please bear with me, and keep in mind you may have to FReemail me more than once for me to get it done. Thanks again!]

[xJones]

Well, dang. George Bush has gone too far this time.

[petuniasevan]

Thanks for the ping, mhking!

Rudder, how would you like a REAL article on this subject? I can't stand badly-written blurbs that obviously were the low end of importance in accuracy to the editors, either.

All the links should work. Enjoy!

The Sagittarius Dwarf Elliptical Galaxy, SagDEG

Dwarf Elliptical Galaxy SagDEG (also Sagittarius dSph) in Sagittarius

Right Ascension	18 : 55.1 (h : m)
Declination	-30:29 (deg : m)
Distance	80.0 (kly)
Apparent Dimension	190x490 (arc min)

In 1994, R. Ibata, M. Irwin, and G. Gilmore found this small Local Group galaxy by stellar brightness density investigations (see also e.g. the August 1994 issues of Astronomy or Sky & Telescope or the German Sterne und Weltraum). This galaxy was immediately recognized as being the nearest known neighbor to our Milky Way, significantly closer than the Large Magellanic Cloud which was considered to be our closest companion until than.

This dwarf galaxy is called SagDEG (for Sagittarius Dwarf Elliptical Galaxy), or sometimes Sagittarius Dwarf Spheroidal Galaxy; don't confuse it with another member, SagDIG (Sag. Dwarf Irregular Galaxy). It is strongly recommended to avoid misleading designations such as "Sagittarius Dwarf" (which is an older designation for SagDIG), "Sagittarius I Dwarf", or similar ambiguous names for this galaxy, although they occasionally occur in websites, databases, articles and papers.

These are two minor galaxies in the same constellation Sagittarius, which are of different type: The difference between these types is that dwarf irregulars still have interstellar matter and/or young stars while the dwarf elliptical have only an old yellowish stellar population. From its stellar contents, it is resembling other low surface brightness members of the local group such as the Sculptor dwarf galaxy, but it is so highly obscured that it was hidden up to the 1994 investigation.

SagDEG is one of the most recently discovered members of the Local Group, and is currently in a very close encounter to our Milky Way galaxy. It is apparently in process of being disrupted by tidal gravitational forces of its big massive neighbor in this encounter. Nevertheless it is apparently big: 5x10 degrees in the sky.

Globular cluster M54 coincides with one of the galaxy's two bright knots, and is also receding at about the same velocity. It may also be at the same distance (about 80,000 light years), so probably M54 is the first extragalactic globular ever discovered (by Charles Messier in 1778). When SagDEG will be disrupted after the current encounter, M54 and the other at least three globulars of this dwarf (Arp 2, Terzan 7 and Terzan 8, which are all much fainter than M54) will be the "remnants", while the other stars will be spread over the galactic halo, or escape as intergalactic travelers. The globulars will perhaps be captured and find their place in the halo of the Milky Way galaxy. There is already one Milky Way globular cluster which is suspected to have been captured from SagDEG: Palomar 12.

In February 1998, a team of astronomers headed by Rosemary Wyse of John Hopkins University found that SagDEG orbits the Milky Way Galaxy in less than one billion years. Because it must have passed the dense central region of our Galaxy at least about ten times, it is surprising that the dwarf has not been disrupted for so far. Astronomers suspect that this fact is an indication for significant amounts of dark matter within this small galaxy, which ties the stars stronger to the galaxy by its gravity. We have their press release here, or you can read their original report online.

[petuniasevan]

Oh, come on now. I put your name in the TO: line of the previous post.

The posting gremlins must have erased it.

Thanks for the ping!

[wku man]

Oh, gimmie a break...gimmie a break...break me off a piece...

Scouts Out! Cavalry Ho!

[bedolido]

that's amazing. Thanks for the post.

[King Prout]

on that note, is it just me or is the "Enterprise" opening theme even more irritating and trite this season than it was originally? The canned banjo(?) and synth-drum additions put it over the top (under the bottom?).

[mhking]

on that note, is it just me or is the "Enterprise" opening theme even more irritating and trite this season than it was originally?

Not just you - it sounds even more like a "lite rock radio" reject. They were supposed to commission some other group to do the theme for this season, but from what I've heard, the new theme was rejected in favor of the "remix" version of "Faith of the Heart." [rolling eyes]

The first episodes of "Star Trek: Enterprise" (yep, the title change is official as of last night) this season were pretty good, but when I saw the previews for next week touting the alien sex slave (!?), I was pretty much ready to throw in the towel.