APOD: Sideways Galaxy NGC 3628 (2008 May 15)

[iampete]

http://apod.nasa.gov/apod/ap080515.html

Regarding image http://antwrp.gsfc.nasa.gov/apod/image/ ... rocchi.jpg.

The very abrupt edge, i.e., the distinct rectangular shape (especially of the left edge), of the pictured galaxy is completely counter-intuitive to me.

Is there an explanation why there would exist such a distinct, abrupt edge?

Thanks

[Sputnick]

Apod featured a square galaxy some time ago . . there seems no limit in Creation's creations. I've never seen a galaxy 'sag' like this one, and suspect it's sagging towards another galaxy. Too bad we don't have a larger picture.

Actually .. the abrupt edge fits my 'time funnel' theory .. and I think that's how the square galaxy got squared .. by being in the centre of four time funnels created by four galaxies. The four sides of the square were slightly concave.

[iampete]

Sputnik -

Yes, I recall previous illustrations of a square galaxy, and, if memory serves, the explanation was related to the alignment of galactic matter along field lines apparently emanating from the galactic center, coupled with view angle effects and some such. That one I could understand from a "doesn't sound totally unreasonable to me" point of view. This one just doesn't fit in with anything I am familiar with.

You've mentioned your time funnels several times in various threads. I have yet to see an (understandable to me) explanation (even at a conceptual level) that satisfactorily describes what they actually are, how and why they might be formed, what their essential characteristics are, what their interactions with other celestial objects might be, and how it might be possible to determine that they actually exist. For these reasons, the time funnel "explanation" doesn't work for me.

I'm not saying that you're wrong, only that your explanation does not satisfy me.

Pete

[iamlucky13]

Normally galaxies seem to have a roughly Gaussian distribution radially from the center, as well as at a distance from the ecliptic plane for a given radius.

In this case, it seems the latter tendency is the one that breaks down the most. My guess would be it's due to a gravitational interaction with another galaxy that may have fanned stars out away from the ecliptic.

One of the links in the caption roughly agrees with this:

http://www.aao.gov.au/images/captions/aat063.html

[BMAONE23]

Another possibility is the line represents a PNR (point of no return) for the central gravity well and that the matter beyond that point has been ejected from the host.

[iampete]

. . . My guess would be it's due to a gravitational interaction with another galaxy that may have fanned stars out away from the ecliptic.
One of the links in the caption roughly agrees with this . . .

I read that but I just can't picture how that would result in that kind of shape.

Another possibility is the line represents a PNR (point of no return) for the central gravity well and that the matter beyond that point has been ejected from the host.

I thought of that, but my problem remains that it's pretty close to a straight line. I would expect a PNR to be a circular arc centered on the galactic center (or very close to it, as the other gravitationally interacting galaxies are much farther away).

The radius of curvature appears much, much greater than the distance to the galactic center.

[neufer]

. . . My guess would be it's due to a gravitational interaction with another galaxy that may have fanned stars out away from the ecliptic.
One of the links in the caption roughly agrees with this . . .

I read that but I just can't picture how that would result in that kind of shape.

Another possibility is the line represents a PNR (point of no return) for the central gravity well and that the matter beyond that point has been ejected from the host.

I thought of that, but my problem remains that it's pretty close to a straight line. I would expect a PNR to be a circular arc centered on the galactic center (or very close to it, as the other gravitationally interacting galaxies are much farther away).

The radius of curvature appears much, much greater than the distance to the galactic center.

What if we are observing a barred galaxy perpendicular to the bar and in the plane of the galaxy:

http://antwrp.gsfc.nasa.gov/apod/ap070315.html
http://antwrp.gsfc.nasa.gov/apod/ap070328.html
http://antwrp.gsfc.nasa.gov/apod/ap060827.html

[iampete]

What if we are observing a barred galaxy perpendicular to the bar and in the plane of the galaxy:

http://antwrp.gsfc.nasa.gov/apod/ap070315.html . . .

I guess that could work for me (although parallel to the bar would seem more likely to me), except for the caption which indicates that it is thought to be a spiral galaxy.

[BMAONE23]

It is certainly a Unique Individual

[NoelC]

I hate to state the obvious, but I see nothing overly rectangular about this galaxy, nor counter-intuitive in its shape. I will agree it seems somewhat jumbled.

Frankly, my first impression is that it's not exactly edge-on, but a few degrees tilted.

Remember that we're looking through a somewhat/mostly transparent object nearly edge-on. Think of it as looking at an X-ray.

And it's possible it's in the last stages of merging with another one. That might explain the odd splash of (millions of) stars out this way or that, and why it doesn't appear narrow at the edges as many edge-on spirals do.

-Noel

[bystander]

http://antwrp.gsfc.nasa.gov/apod/ap080515.html

I think interaction with M65 and M66 (the other two galaxies in the Leo Triplet) explains the distortion and tail.

[Sputnick]

Sputnik -

"I have yet to see an (understandable to me) explanation (even at a conceptual level) that satisfactorily describes what they actually are, how and why they might be formed, what their essential characteristics are, what their interactions with other celestial objects might be, and how it might be possible to determine that they actually exist."

Pete

Pete - I hear what you're saying; and I sure wish I could translate my intuitions into understandable information because then I probably wouldn't have to push a broom and clean toilets on the weekend to earn a little extra money .. but Thanks for saying my concept dwells in the realm of possibilities.

[astrolabe]

Hello iampete,

I agree with the idea of interaction with other galaxies and even though the edge looks roughly squared off it could be that instead of losing material (which probably did occur to an extent) the effects of it's neighbors may have caused a "burst" of star formation that filled out the otherwise tapered edge of the spiral.

However, I also need to look into images that more encompasses that area of space. I like the barred spiral suggestion as well.

[astrolabe]

Hello Sputnick,

Nice to see you back, some galaxies do demonstrate jets at the poles in visible light...who's to say how many there are in invisible spectrums. I'm sure they are known about and studied in depth. Even if one could not view a time funnel in any spectrum (what would time look like?) in some instances all someone may have is an observable effect or influence by something unseen. I wonder SR predicted such a phenom?

[bystander]

... I also need to look into images that more encompasses that area of space ...

Here's a good look: APOD: 2007 July 27 - The Tidal Tail of NGC 3628

[orin stepanek]

I wonder what this galaxy would look like from above; rather than from edge on? That might explain a bit??? Unfortunately we don't get that option.
Orin

[Sputnick]

Hi Astro,

Yes, nice to chat with you again, also. I was temporarily 'absent' only because I didn't see anything on apod that stirred my curiousity.

From my point of view at this time we can't see time, but we can see its effects in my famous 'trailing spirals' of spiral galaxies which appear to be 'following' the galaxy core's forward motion when the galaxies' faces are viewed .. while spirals appear to be flat when viewed from the edge.
What we are seeing in a 'trailing' spiral is where the spiral was .. not where it is.

I'm also considering the lesser possibility that the spirals may also appear to preceed the core .. so that the spiral appears to be where it will be .. an either or situation .. and of course that raises the possibilty that time flows in both directions. I think though, that time is more circular, or even globular, with the same event eventually meeting up with itself; but if it is linear I think the same event could possibly be found anywhere along the line, or is occuring at all points on the line. I also think that when this universe ends and another begins time will cease to exist .. therefore the time 'line' is not infinite .. Alpha and Omega being One and the same.

Meanwhile .. it's time to end this post before I make myself even dizzier trying to conceptualize in 77 dimensions.

[astrolabe]

Hello Bystander,

Thank you! Remarkable photo, sometimes nebulas, and other color-enhanced images make me forget the beauty of the black background of space. Especially when objects such as the Leo Triplet are viewed. I've also been looking at past APODs regarding the jets of Centaurus A. Unbelievable!!

[harry]

Greetings from the land of ozzzzzzz

Bystander was correct the influence of other galaxies has caused it spiral to deform.

Sideways Galaxy NGC 3628
http://antwrp.gsfc.nasa.gov/apod/ap080515.html

The distorted shape and faint tidal tail suggest that NGC 3628 is interacting gravitationally with the other spiral galaxies in the Leo triplet, M66 and M65.

Trio Leo
http://antwrp.gsfc.nasa.gov/apod/ap060309.html

All three are large spiral galaxies. They tend to look dissimilar because their galactic disks are tilted at different angles to our line of sight. NGC 3628 is seen edge-on, with obscuring dust lanes cutting across the plane of the galaxy, while the disks of M66 and M65 are both inclined enough to show off their spiral structure. Gravitational interactions between galaxies in the group have also left telltale signs, including the warped and inflated disk of NGC 3628 and the drawn out spiral arms of M66

The Tidal Tail of NGC 3628
http://antwrp.gsfc.nasa.gov/apod/ap070727.html

In fact, fellow trio member M65 is near the bottom edge of this deep cosmic group portrait, with M66, just above it and to the left. But, perhaps most intriguing is the spectacular tail stretching up and to the left for about 300,000 light-years from NGC 3628's warped, edge-on disk. Know as a tidal tail, the structure has been drawn out of the galaxy by gravitational tides during brief but violent past interactions with its large neighbors

APOD: 2004 April 7 - Unusual Spiral Galaxy M66
http://antwrp.gsfc.nasa.gov/apod/ap040407.html

APOD: August 12, 1996 - Leo Triplet Spiral Galaxy M65
http://antwrp.gsfc.nasa.gov/apod/ap960812.html

This reminds me of the last TANGO in Paris.

[Sputnick]

I just read about a (to me) recent discovery of normally invisible superheated gas connecting galaxies which would not be considerered 'close neighbours' .. the author (in Scientific American I believe it was) was speculating that this gas might be part of the Dark Matter factor.

[gwrede]

The article says "The distorted shape and faint tidal tail suggest that NGC 3628 is interacting gravitationally with the other spiral galaxies in the Leo triplet".

I'd say both the distortion and the tidal tail remnant are /not/ from interaction with the other Leo triplet galaxies. To me the shape suggests that they both are results from a galaxy collision. The collision is so long ago that the galaxy has returned to a circularish form, but the other galaxy obviously has come from a direction not in the plane of the resultant galaxy.

To me, the square cross section indicates that stars are still undulating about the plane of the galaxy, way after the radial form has become almost restored.

[harry]

Hello Sputnik

Gravity connects all.

There is a theory that electromagnetic waves also have an influence at close encounters. This inteconnection is shown in many images.

We know of jets from BH that go out for millions of light yrs.


http://chandra.harvard.edu/photo/2007/3 ... nim_lg.mpg

http://chandra.harvard.edu/photo/2007/3 ... c438_radio

Plasma properties play a very important part.

http://www.electric-cosmos.org/electricplasma.htm

======================================
3C438:
Galaxy Cluster Takes It to the Extreme
http://chandra.harvard.edu/photo/2007/3c438/

In this side-by-side comparison, an apparently ordinary star field in optical light (left) is shown to be dramatically different when observed in X-rays (right). Chandra's image of 3C438, the central galaxy within a massive cluster, reveals evidence for one of the most energetic events in the local Universe. An arc-like feature to the lower left in the cluster's hot gas is about 2 million light years long. VLA Radio Image of 3C438 Astronomers have determined that an enormous amount of energy would be required to produce such a large structure. One plausible scenario is that two massive clusters collided at high velocity and later merged. This would have created a shock front in the hot gas that could account for the ridge seen in the Chandra data.

See the movie,,,,,,,,,,fantastic

[Sputnick]

Wow, Harry, marvellous, thanks!

I see the strength of plasma as support for my rivers of stuff flowing and creating whirlpools which are the galaxies. Perhaps that's why you pointed me to the reference? If the Galaxies were created from the 'outside', by currents of a plasma like energy rubbing borders at different speeds that could explain why the stars in the arms travel at different velocities from inner stars. On a small scale, if the solar system is created by currents from the 'outside', the pressure of the 'plasma' could be a factor in the the Pioneer Anomaly which seems to suggest the further out Pioneer went the more 'resistance' it met.

My goodness - I just went back and read plasma further - "The Sun may be powered, not from within itself, but from outside, by the electric (Birkeland) currents that flow in our arm of our galaxy as they do in all galaxies." Oh my goodness .. I could be right after all.

On a lighter note, do you think Fairie Dust "Fabricated Ad hoc Inventions Repeatedly Invoked in Efforts to Defend Untenable Scientific Theories" (FAIRIE DUST) could be the cause of the strange, bright light suddenly flowing and dancing and fluctuating in the basement room outside of my basement computer room as I was in the midst of reading the plasma reference, or is it simply the sun's early sunset rays streaming through windblown trees and entering a groundfloor window at the proper angle to swim down the stairway into that room outside of this dark room? The light was so strong I was frightened I had an electrical fire .. took me nearly instantly away from the Asterisk .. but first I listened for the hizzsslings, but was met with silence only, so knew there had to be another explanation .. like God declaring himself.

I disagree with Jim Peebles when he says "It's an embarrassment that the dominant forms of matter in the universe are hypothetical..." Perhaps he was speaking humourously .. but I don't think hypothetical anything is an embarrassment. We must at times reach out with imagination to visualize what may be, and then look for answers as to why it is or is not.

If you've read this far, thanks again for the wonderful references - and I hope your days and evenings are pleasant.

[Sputnick]

Also then the sun instead of 'burning' nuclear fuel may be creating it - the core growing larger and larger until it truly explodes - the cause of supernovas (?) Is there some way to measure the growth of dense matter at the core? As the matter grows, gravity would increase? Do we have instruments capable of such measurements? Have measurements already been made? If the sun's gravity is increasing, the speed of the earth in its orbit would also increase? Has that increease been measured?
SO many questions.

[astrolabe]

Hello gwrede,

This is a laid-back reminder that if you're posting a new thread on an already existing topic it can appear out of context and unrelated to an ongoing discussion so try to reply within the ongoing thread.

Your comment maybe feasible but I don't know a lot about the dynamic of such things. I did see a recent APOD with two galaxies almost totally combined so maybe that's what we're seeing here.

Welcome to the Forum!