Anomaly in CG4 image? (APOD 06 Aug 2007)

[Galactic Groove]

roger that

you asked for people's opinions and you got answers. of course most are going to side along with BMAONE23's response, it's the most logical.

you're right, there could be something causing the lensing effect and that "ring" of stars could infact be only 1. But looking at known examples of lensing and seeing what the visual effects are, we would be lead to believe that isn't the case here. Lensing distorts the light in many ways. See these links for examples...

http://antwrp.gsfc.nasa.gov/apod/ap011007.html
http://antwrp.gsfc.nasa.gov/apod/ap060524.html
http://antwrp.gsfc.nasa.gov/apod/ap040217.html

and my favourite...
http://antwrp.gsfc.nasa.gov/apod/ap070311.html

Perhaps your hypothetical question was just to easily answered which is why you don't seem to appreciate the consensus of everyones opinion (which is that the first answer that was given to you is correct). I dunno, but we do applaud your attempt to open up dialogue and probe people's minds. On occassion, someone really will have some serious insight that most others will not have thought of, but again... Only On Occassion. No think-tank you consult will yield that result everytime.

PS:

Yo, children - you cannot know what a thing is until it has been properly investigated! Until then, you are merely guessing.

Thanks Einstein! Then why are you expecting more than an educated guess from people that either haven't investigated it, or simply can't?

[Chris Peterson]

Suppose there were a neutron star, or maybe even a black hole somewhere near the visual center of that group. Then, suppose there may be some other objects between us and that thing. Wouldn't an observer see something much like that?

No. Gravitational lensing doesn't produce point sources. Optically, gravitational lenses behave rather differently from ordinary lenses. And the zone of lensing around a black hole is very small- just a fine ring around the event horizon. There is no way that a black hole could create such a large ring of distortion, especially as these stars are very close to us. When we see gravitationally distorted images, we are seeing galaxies millions of light years distant with their light path bent through a very small angle by an intervening galaxy.

By far and away the most likely mechanism to explain this asterism is simple chance. But in any case, there is nothing about it that is remotely consistent with gravitational lensing.

[geckzilla]

I just realized that jimmy said what I wanted to say much earlier in this thread but in about 3 sentences. I suck.

[jimmysnyder]

I just realized that jimmy said what I wanted to say much earlier in this thread but in about 3 sentences.

Don't kick yourself around too much:

I am sorry for the length of my letter, but I had not the time to write a short one. - Blaise Pascal

[Andy Wade]

Many thanks to you all. You have provided me with a modicum of entertainment, along with confirmation of certain secret opinions of mine.

On the one hand, if there is clear evidence that this is one thing and not another, a brief summation will (probably) suffice, and I'll toddle off, sucking my thumb and pulling my little red wagon behind me.

On the other hand, when most of what I get for an innocent question is either condescension or outright mockery, I hope I'm intelligent enough to understand that I'm in the wrong place to find original thought.

No-one is here to entertain you, and we can all make a contribution in whatever way we see fit. We are allowed to have a joke occasionally. It's not really for you to come here in your first posts and make comments which quite frankly come across as condescending.
And you're still doing it from what I can see.

Secret opinions? - my ar5e.

You asked a question in a way which seemed reasonable but then started to respond to the answers in a way that I personally found a bit off.
If you're going to make a joke, use a smiley. That's what they are there for.
Have you ever heard the phrase:
"You catch more flies with honey than vinegar" ?

Lighten up and you'll get a better response from people.

If you have a point to make, please make it clearly, then we 'lesser mortals' might be able to understand whatever it is that you're banging on about.

Or maybe some people are taking an instant dislike to you simply because it saves time...

[azutjw]

OK, I can see some apologies are in order, and maybe a clarification or two. If I came across as a bit high-handed out of the gate, that was not my intent. I am an engineer, and when someone cuts me short with what I see as an over-simplistic answer, I take umbrage. Apparently I was expecting far too much acceptance far too quickly. I'm sorry; I am elderly, and a bit impatient. I did not, do not, and will not intend to offend. That being said, there are some responses in order.

Andy Wade: I did not imply that I felt your - or anybody's - primary purpose was to entertain me. Further, I am entertained by intellectual discussion, especially those that foster thinking in new ways about old things. Also, we need to reach agreement on the usage of "condescending". My intent was the secondary (or tertiary) definition, exhibiting a patronizing or superior attitude. I fail to see how you can impute that to me. Or perhaps this paragraph is an example? You, sir, are far too sensitive. And please keep the opinions of your "ar5e" out of it, secret or otherwise. If you consider taking an instant dislike to someone a reasonable action to save time, commend me, you have inspired me.

Chris Peterson: Thank you for a reasonably clear and explanatory response. I have only done a little work with optics, I know my understanding is minimal. Why do they have to be point sources? Or is that just a relative term? Why do you say a gravitational lens is so different from an ordinary one? The light is bent due to a relationship between entry and exit angle, with the amount of warping being dependent on the nature of the lens medium. Also, I did not restrict the cause to black holes only, I included neutron stars, hopefully allowing the consideration of any object of sufficient density. Regarding the known examples and their generation by super-galactic distances and masses, does that mean it couldn't possibly happen on a near and smaller scale? With my admittedly limited understanding of astrophysics, I think it is a reasonable - though certainly more rare - possibility.

Galactic Groove: Thank you also, for a response more on a par with my intentions; you reassure me - perhaps the fault is not entirely mine - just mostly, something I can accept. However, I do not see why the entire ring must be originating from 1 star. Wouldn't it be more likely that a number a stars were scattered along the visual axis, with slight but varying normal offsets? I seem to remember seeing similar effects generated by 'ordinary' lenses. Not exact, but similar. And thanks ever so much for the links to APOD examples, they have joined my collection in a folder I have titled "Astronomalies". Lastly, I have a hard time buying into "can't". In my experience, there are occasions when it's true, but usually it's a cop-out. And especial thanks for the applause - considering the majority of the rest of this thread, it warms me.

jimmysnyder: Apparently the history lesson was wasted. The "imagine" quote is from Sir Arthur Eddington, and I wholly agree with him. I am sorry I don't have the time to draw for you a simple 2/3-D sketch offering the fruits of my imagination. Again, I am not suggesting a single star as the source of the entire - what, circulipse? Again, I consider ALL 'constellations' to be asterisms by strict definition. My first thought was that something this small and this clear just might be something else. Finally, you have a rather restricted idea of how science is done. If you can state a clear question, it's science. If you can find a clear answer, it's science. If you spend time and energy looking at various possibilities trying to find a clear answer, it's science. Even if all you find is more questions, it's still science. Also, engineering is science, although I wouldn't expect a software person to understand that. I am working now at a company that is developing an experimental aircraft, planned to do things that have not been able to be done previously. The swiftest make the most mistakes. "Slow and steady wins the race." When a thing hasn't been done before, it's always because someone wasn't trying the right combinations.

To all: Remembering what was done and said to Copernicus, Galileo, Columbus, Colt, Steward, Fulton, Ford, Tesla - and let us not forget DaVinci - my confidence in 'accepted knowledge' is marginal. I believe any question at all is a good one, and I am entertained by seeking answers.

If this has been far too verbose - - sue me.

[geckzilla]

I became curious to find the other circles in this image since, by luck, the particular circle in question had the good fortune to not receive any bright foreground stars to steal attention from it, or many background stars, or galaxies, or clouds or anything to obscure its intensity. So to aid the weaker (or more distant, or more obscured), less fortunate circles, I have decided to hunt them down so that you can more easily see them.

I also noticed a few non-circles, such as a nearly complete square, a perpendicular pairing of 3 pairs of double stars, and some seemingly mirrored triangle or trapezoid shapes. It's only fair that they get pointed out too. There is even a mini circle within your big circle (though it is not easily seen at this resolution)



Also, in case you would like to study it further, I have found an image of the same globule at twice the resolution which also includes your circle. It is available for download here.

[Chris Peterson]

Chris Peterson: Thank you for a reasonably clear and explanatory response. I have only done a little work with optics, I know my understanding is minimal. Why do they have to be point sources? Or is that just a relative term? Why do you say a gravitational lens is so different from an ordinary one? The light is bent due to a relationship between entry and exit angle, with the amount of warping being dependent on the nature of the lens medium. Also, I did not restrict the cause to black holes only, I included neutron stars, hopefully allowing the consideration of any object of sufficient density. Regarding the known examples and their generation by super-galactic distances and masses, does that mean it couldn't possibly happen on a near and smaller scale? With my admittedly limited understanding of astrophysics, I think it is a reasonable - though certainly more rare - possibility.

I see nothing to suggest that the objects in the circle are anything but stars, which are effectively point sources. But regardless of whether your hypothetical background object being lensed is a star or a galaxy, a gravitational lens wouldn't focus it to a point (or points). A normal lens doesn't refract light passing through its center, and the angle of refraction increases as you move away from the central axis. This is completely unlike a gravitational lens, which exhibits maximum refraction at the center, which drops off with distance from the distorting mass. So a gravitational lens doesn't have a focal point in any ordinary sense. That's why we see arcs and odd caustic-like images, not points.

I don't really see any way that you could have significant gravitational lensing nearby, where the objects were in our own region of the galaxy. Because the deflection angles are so small, the distances between the viewer, mass, and source has to be very large. A black hole will only distort light significantly over a range on the order of its radius (and a neutron star much less). And that black hole is only a few kilometers across in the first place- unresolvable from Earth. The sort of microlensing that people are looking for manifests as a photometric effect, not something that can be spatially resolved in an image.

[bystander]

If you check the apod, the circle of stars is not so circular, and the center isn't so blank.

So, if it isn't geometrically perfect, it must be irrelevant.

If you had taken a look at the apod that was posted, (http://apod.nasa.gov/apod/ap060314.html, quite possibly the same picture geckzilla used above), maybe you would have gotten the point. If I look at the picture geckzilla posted (better picture than http://antwrp.gsfc.nasa.gov/apod/ap070806.html), it is apparent to me that we are looking at an asterism.

Don't be so ready to dismiss someone simply because they disagree with you. That is definitely NOT scientific.

[Sputnick]

Thse starry circles - if they aren't optical defects, and are real formations of stars, the stars could have been positioned by the currents of Dark Matter and Dark Engery at the edges of time funnels .. and if anyone wants to call me a nut bar that's okay too, a pretty good generalization, really .. but I think my ideas are probably right.

[NoelC]

azutjw wrote:

Also, engineering is science, although I wouldn't expect a software person to understand that.

I feel compelled to respond to this point, as it offended me.

I'm a career software engineer and I'll wager I can do and have done a lifetime of engineering work at or beyond the level of quality and precision you're capable of.

From where I sit it is becoming clear that you:

1) Are not really a people person.
2) Consider yourself smarter than thou.
3) May in fact feel empowered by hiding behind a handle - azutjw.

I'm no one to judge, but frankly I find myself amused that a person who can write as clearly as you do can't seem to put 100 words together without offending whole groups of people. And in an "Apologies" post no less. It is no surprise that some people feel this is not accidental.

With only the best intentions, please let me suggest that a touch of humility might help you here - and in all walks of life.

Please pause for a moment to think that some if not many of the people participating in this forum may - *they just may* - have a better grasp of what's going on in the cosmos than you do. Whatever you feel you have learned from a lifetime of aircraft engineering just might not mean squat on a cosmic scale. And none of us can, or ever will be able to, go "out there" and check in person.

The more we try to understand, most of us start to understand just how little we understand, and ultimately how little we CAN understand.

-Noel

[Sputnick]

I agree with Noel, Azut, that you can say things in an abrasive, and perhaps even non-intelligent way. Software is engineering. I think what has happened is that you have been attacked by one astronomy buff, as I was attacked by one exceptionally rude person here (but only one), and you have grouped the astronomy buffs in an unpleasant grouping. My experience is that they are curious and intelligent and friendly, a great bunch, except they aren't taking my time funnels and Currents seriously, and will therefore be greatly surprised when a major Discoverer (shortly) claims for their very own MY FRICKIN" DISCOVERY for which I won't receive any fame .. poor, poor me.

[azutjw]

In looking for responses to a more recent thread(s), I discovered a couple of posts to a thread I thought was closed.

OK, maybe I really am a self-righteous, overbearing, ignorant jerk. Strange that I have managed to have a fairly successful career in a field that absolutely demands interaction, shared ideas, and constructive criticism.

So, how about if I plead total ignorance and general confusion, and ask that perhaps someone will take the time to expound on the relationships of self, argument, attack, reason, debate, acceptance, presumption, and the difference between infer and imply?

Or was that too condescending? Or too pointed? Or too vague?

For instance:

jimmysnyder Posted: 20070927:1923

azutjw wrote:
The real question I was trying to introduce is "How do you know for certain that that isn't what it is?"

That is not how science is done. Nothing is for certain. It's not even how engineering is done, where even though the race is not always to the swiftest, that is still the way to bet.

azutjw responded on 20070928:1521

Also, engineering is science, although I wouldn't expect a software person to understand that.

I think the intent - and the language - was to acknowledge that a "software person" would not be likely to be familiar with the processes of mechanical engineering.

Clearly, that intent was not effectively communicated.

Quite a bit after the fact
NoelC Posted: 20080503:2131

I'm a career software engineer and I'll wager I can do and have done a lifetime of engineering work at or beyond the level of quality and precision you're capable of.

At what point does a posting become a (self-serving) personal attack?

NoelC continued

From where I sit it is becoming clear that you:

1) Are not really a people person.
2) Consider yourself smarter than thou.

????

and then said

I'm no one to judge, but

!!

frankly I find myself amused that a person who can write as clearly as you do can't seem to put 100 words together without offending whole groups of people. And in an "Apologies" post no less. It is no surprise that some people feel this is not accidental.

Umm - does he write clearly or not?

Is this entire post a personal attack, or a gentle social instruction and I'm the flamin' idiot?

Does what anybody knows "mean squat on a cosmic scale"?

Then, just to get back to what I thought was the purpose of this forum - -

All my math classes, statistics, data interpretation, etc. defined a "point" as a dimensionless location. How can something as large as a star be called a point?

This is something I have never understood! We speak of a black hole as having various masses, yet say its density is infinite. We define a Swartzchild radius, yet say it is a point. It seems to me that if you cannot obtain detailed information from inside a given 3-dimensional radius, then that radius is where the phenomena begins. How can you say the surface is elsewhere? If the density is truly infinite, how can you calculate either a volume or a mass? Conversely, if you have a 'defined' volume of space, and a known mass within it, doesn't that get you - by definition - a finite density?

Please explain.

In some detail, directed toward an admittedly simple mind.

+++++++

Finally, a note to all:

"azutjw" is not a 'handle', it is who I am and where I'm from. It's not even a code. If you have not the wit to interpret it correctly, and lack the decency to query the originator...kindly keep your idiotic speculations to yourself.jw

[Sputnick]

Azut - I'm a very tolerant, forgiving and understanding person .. but you're way overboard with your rants .. this is a science forum, not a group session for self-obsessed paranoid schizophrenics .. perhaps you should try a mental health forum to exchange your opinions about the mind, and concentrate on astronomy while in this forum.

[azutjw]

im so sorry - i certainly did not mean to start personal wars -

what about the technical questions?

or is the change of subject schizophrenic?

[Sputnick]

Well Azut .. there are many differences of opinion so it's not worth getting upset if someone disagrees.

By the way .. this aircraft you're working on, it wouldn't be a disc, would it, controlled by thrust vectoring? With a spinning outer edge for stability
and glide ability in case of loss of main power? I've often thought that would be the ultimate aircraft.

[Doum]

I see a schizophrenic dialogue between the same person. Gee may be it's contagious.

[Sputnick]

Maybe you're a dork, Doum. I'm out of this conversation.

[astrolabe]

Hello fellow Schizes,

Okay, this is the Forum- not the Colosseum- so lets put the tridents, nets and swords away, put on the togas, and head back to the civilized Senate. I hear tell an interesting dialog is about to occur between Julius and Brute.

OOPS! Was I being indelicate? All I can say is: jw, I'm glad I didn't ask that Question!

[NoelC]

My response was not a personal attack, though I confess to being a bit miffed. Perhaps I'm a bit sensitive to being considered "less than an engineer" as I have chosen to do software work. My turn to apologize.

However, my advice is genuine and well-meaning: If you play humble for a while on a forum until the "regulars" get to know you and respect you, you will find you're more warmly accepted than if you jump in and start acting like you own the place.

Not sure where your questions on "point" originate, but please let me try to offer my meager thoughts on the several uses I know where the word is used as relates to stars and other cosmic things...

Stars are considered "point light sources" because they may be large, but they are SO incredibly, amazingly, stunningly distant that all but the VERY closest and most huge cannot be resolved into anything but an infinitessimally small point of light by even our most powerful telescopes.

Regarding singularities... Does anyone really know what's in a black hole? Is matter really compressed to a dimensionless point - a portal to another universe, perhaps? Would it make any external difference if the matter within an event horizon just filled the space, or were collasped to a point?

Oh, and philosphers may need to be called in to define what constitutes this universe and what's another one. No one I know of has been to another one (though some would say the children of the '60s might have gotten close).

Has anyone described a black hole nicely using mathematics that aren't based on a host of assumptions?

Personally I'm fond of thinking that screwy things happen to time inside a black hole's event horizon - it may even stop utterly or go backwards! That would handily explain how no light can get out.

Perhaps I'm more philosopher than scientist.

If it's of interest, there was an APOD a while back that described the observed motion of a star that came within light-hours of the supermassive black hole surmised to be at the center of our Milky Way galaxy. Ah, here it is: http://apod.nasa.gov/apod/ap021018.html

-Noel

[azutjw]

NoelC:
Thanks, we're cool. IMHO 'engineers' in general are any people who use formal protocols to answer questions and/or build new things and/or improve old ones. I'm aware of the common exclusion based on collegiate degree, and the other based on particular discipline, and I subscribe to neither. It's been my great good fortune to have worked with more than one excellent "non-degreed" engineer, and my loss to have worked with a couple degreed idiots. As I said before, I'm used to criticism - in mechanical engineering it is so regularized it is called simply "checking" - I generally don't take things personally until they get excessively personal.

Back to the subject...

My questions on "point" originate with simple ignorance of the common lexicon: my definition of 'point' goes back to Euclidean geometry; I have always considered that definition 'absolute', and 'absolutely precise'. If some discipline requires an expansion of that definition, that's OK with me (as though it matters...), I would just like a fairly clear statement of the new (to me) inclusion. I'm still not very comfortable with it. It seems to me that science should be at least attempting a precise, consistent description of the cosmos, and if a 'point' is dimensionless in one context, the word should be considered that way at all scales - after all, it is only a matter of scale, and we know very well that all stars occupy definite volume.

Regarding the 'black hole' thing, I must again plead ignorance; I've been basing my discussions on terminology "taught" at the undergrad level, and I should have thought this would be significantly simplified. A recent excursion (last night) through this lovely forum, and following up leads and links, presented discussions of densities of 'black holes' in the 10^20 - 10^30 Kg/m^3 range, with different effects from the 10^35 - 10^50 Kg/m^3 range. And no mention at all of 'infinite' densities.

So maybe I'm not so far off base after all...obviously, though, there is an awful lot I don't understand, even of what I think I understand, so if anyone out there would take pity on me, the whole reason I'm here is to try to rectify that...to some degree...jw

[NoelC]

Euclidean geometry may just be an approximation of cosmic reality. One that works nicely nearby, but out there...

General/special relativity seems to be a better approximation....

However, there's that dark matter stuff people seem to want to invent to explain things when the latter approximation goes awry. Personally I think the math is still wrong; perhaps there are factors at work on a truly cosmic scale that haven't been taken into account.

Personally, I'm still trying to get my head around what space-time means. Doggone brain keeps wanting to oversimplify the problem and think of the 3 dimensions of space as fixed while time fluctuates.

Back to your original observation... A seemingly unlikely alignment of stars - in a circular pattern or whatever. There are some generally accepted theories that essentially describe a process where stars form from interstellar gas/dust after the stuff has been perturbed. This perturbation can happen as a result of an explosion (e.g., supernova), or gravitational interaction (e.g., colliding galaxies). In any case, it seems likely to me that it might happen along a "front" or "surface", given that blast waves (and even gravity waves) don't travel infinitely fast.

-Noel