Starship Asterisk*

geckzilla wrote:If it was direct response to "Chinese occupation and subjugation" it would be a lot more different, don't you think? Unless you suppose they were just a little upset by such actions and decided that rabbits were out and cats were in.

Cousin Ricky wrote:...My tropical sign = Taurus = bull = what I think of astrology. In the avatar, north is 30° clockwise from vertical.
My year of birth = 1963 CE = Chinese year of the rabbit = Lepus.
My year of birth = 1963 CE = Vietnamese year of the cat = Lynx. ...

Tumbleweed wrote:Dark Matter and ordinary matter may affect each other, but to say they are gravitationally bound is a stretch. Ordinary matter affects other ordinary matter in gravity but they are not bound .. if so rockets could not leave earth's gravity field.

How do you account for the warped edges clearly visible in many galaxies?

Did you look into the urls I posted?

Chris Peterson wrote:

Tumbleweed wrote:So you don't believe that the vast majority of the universe (Dark Matter) through which the galaxies move, or in which the galaxies move, is a reality?

Dark matter and ordinary matter are gravitationally bound. There's nothing to suggest that galaxies are moving through larger fields of dark matter. The exception is in galaxy clusters, where the entire cluster supports a dark matter halo. But I've seen nothing to suggest any morphological impact on the galaxies within those clusters (e.g. warped edges or tumbling).

And while galaxies might (and it's far from certain) show motion on more than a single axis, I wouldn't characterize them as tumbling, and I'd certainly not associate it with the influence of any intergalactic medium.

Beyond wrote:You've got all that stuff in that small space? No wonder i couldn't tell anything. But even if i did recognize some of it, i still wouldn't have known what you were talking about, even though i spent almost a year and a half in Vietnam. And what's those two gray rectangles??

geckzilla wrote:

Beyond wrote:
And what's those two gray rectangles??

=

How to use the =

2+2=4

http://en.wikipedia.org/wiki/Robert_Recorde wrote:

[b][color=#0000FF]Robert Recorde[/color][/b]

---

<<Robert Recorde (ca. 1512–1558) was a Welsh physician & mathematician.

Recorde: 1) invented the "equals" sign (=),

• 2) introduced the pre-existing "plus" sign (+) to English speakers and
  3) popularized the name zenzizenzizenzic to represent the eighth power of a number

In his 1557 work _The Whetstone of Witte_ Recorde recorded that
zenzizenzizenzic "doeth represent the square of squares squaredly" .

(The root word for Recorde's notation is zenzic, which is a German spelling of the medieval Italian word censo, meaning "squared".)>>

Beyond wrote:And what's those two gray rectangles??

Cousin Ricky wrote:The Hyades and the Pleiades didn't give it away? (OK, maybe the bits of Auriga and Orion in the field might be confusing.)

MarkBour wrote:

Ann wrote: . . . This galaxy is somewhat bland and poor in star formation. Or, to put it somewhat differently, this flying saucer lacks its red nebulae brake lights.

Ann --
Just wondering. Do edge-on galaxies show us less nebulae in general, or can we see them fine in most edge-on galaxies? I'm wondering if this galaxy is perhaps more rich in them than we can see, just that the dust lanes block our view.

Anthony Barreiro wrote:I don't understand what flying saucers have to do with Vietnamese skylore, nor what connection you have to Vietnam.

Tumbleweed wrote:So you don't believe that the vast majority of the universe (Dark Matter) through which the galaxies move, or in which the galaxies move, is a reality?

Chris Peterson wrote:

Tumbleweed wrote:

Tumbleweed wrote:A very slow clockwise tumble to this galaxy.

P.S. Comparing the mass of the galaxy, the rate of tumble, and the deflection of the leading and trailing edges will give the density of the medium the galaxy is tumbling in. Mathematicians, do your stuff.

Galaxies move in the intergalactic medium, which is far too tenuous to have any effect on the motion of any part of any galaxy. So there's nothing to see along the edges, and galaxies don't tumble at all.

geckzilla wrote: ... you might be able to understand the paper linked to in the APOD description. Hmm, what are these mystical and arcane words?

Rachel, Matthew & Stacy wrote:We present optical long-slit and SparsePak Integral Field Unit emission line spectroscopy along with optical broadband and near-IR images of the edge-on spiral galaxy NGC 2683. We find a multi-valued, figure-of-eight velocity structure in the inner 45'' of the long-slit spectrum and twisted isovelocity contours in the velocity field. We also find, regardless of wavelength, that the galaxy isophotes are boxy. We argue that taken together, these kinematic and photometric features are evidence for the presence of a bar in NGC 2683. We use our data to constrain the orientation and strength of the bar.

geckzilla wrote:Yes, what Art said, and for galaxies like NGC 2683 the stars stop becoming measurable when they blob together. If you can figure out what isovelocity contours and kinematics are you might be able to understand the paper linked to in the APOD description. Hmm, what are these mystical and arcane words? Astronomers are a little magical.

Tumbleweed wrote:

Tumbleweed wrote:A very slow clockwise tumble to this galaxy.

P.S. Comparing the mass of the galaxy, the rate of tumble, and the deflection of the leading and trailing edges will give the density of the medium the galaxy is tumbling in. Mathematicians, do your stuff.

FloridaMike wrote:If we can detect a bar in our own galay which is almost perfectly edge-on why is it hard to tell if near edge-on NGC 2683 has a bar?

Cousin Ricky wrote:The other day on another forum, someone asked if there were any atheists who lent credence to astrology. Of course, the answer is “yes” (however few). If you look at my avatar, you’ll know what my astrological (tropical?) sign is. However, you’ll also know what I think of astrology.

Someone mentioned Chinese astrology, and I responded that if I had a Chinese background, I might use an image of Lepus, although it wouldn’t have the built-in clever pun. But I found myself wondering what constellation I would use if my background were Vietnamese.

Today’s APOD possibly answers that question.

FloridaMike wrote:
If we can detect a bar in our own galay which is almost perfectly edge-on why is it hard to tell if near edge-on NGC 2683 has a bar?

conversely...

If we cannot tell if near edge-on NGC 2683 has a bar how do we detect a bar in our own galaxy which is almost perfectly edge-on ?

http://en.wikipedia.org/wiki/Galactic_Center wrote:
<<The nature of the Milky Way's bar which extends across the Galactic Center is actively debated, with estimates for its half-length and orientation spanning between 1–5 kpc (short or a long bar) and 10–50°. Certain authors advocate that the Milky Way features two distinct bars, one nestled within the other. The bar is delineated by red-clump stars (see also red giant), however, RR Lyr variables do not trace a prominent Galactic bar. The bar may be surrounded by a ring called the "5-kpc ring" that contains a large fraction of the molecular hydrogen present in the Milky Way, as well as most of the Milky Way's star formation activity. Viewed from the Andromeda Galaxy, it would be the brightest feature of the Milky Way.>>

APOD Robot wrote: NGC 2683: Edge On Spiral Galaxy

Explanation: Does spiral galaxy NGC 2683 have a bar across its center? Being so nearly like our own barred Milky Way Galaxy, one might guess it has. Being so nearly edge-on, however, it is hard to tell.....

geckzilla wrote:

MarkBour wrote:

Ann wrote: . . . This galaxy is somewhat bland and poor in star formation. Or, to put it somewhat differently, this flying saucer lacks its red nebulae brake lights.

Ann --
Just wondering. Do edge-on galaxies show us less nebulae in general, or can we see them fine in most edge-on galaxies? I'm wondering if this galaxy is perhaps more rich in them than we can see, just that the dust lanes block our view.

Puffs of hydrogen alpha typically extend beyond dust lanes, ballooning out over time. I'm not sure they're not there. I think this image may simply lack narrowband data.