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Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Mar 25, 2011 8:57 pm
by JohnD
garry wrote:A square shape is not found in nature.
Rare, but found!
See a common UK moth, the Square-spot Rustic, Xestia xanthographa: http://www.gardensafari.net/en_picpages ... grapha.htm

John

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Mar 25, 2011 9:43 pm
by BMAONE23

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Mar 25, 2011 9:47 pm
by owlice

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Mar 25, 2011 9:50 pm
by owlice
Square bacteria

Interesting (four-year-old) conversation Nature is Round, and Humans are Square (though p'haps folks have already found it...).

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 2:07 pm
by hackerspiff
What Is It wrote::oops: Well, another mystery at NASA. Is there anything that they can answer? Everything is a mystery, from this Red Square Nebula , to black holes, to how did the earth form. I would say NASA gets an F for science. Go back to school!
Wow, that's a remarkable attitude. There are yet many gaps in human knowledge of the Universe. That's one reason science is still very interesting... otherwise the field would just be Natural History and Engineering. Ugh.

Also, because the information we can draw from distant objects is just a shadow of all of the details occurring in these systems, we can pose models that explain what we see and yet still be wrong about what is really happening. A well known pysicist (was it Einstein?) once posed this analogy: You give a watch to a group of scientists and ask them to exlplain how it works, but you prohibit them from opening it up. You could get as many different answers back as you have scientists. Each one could propose a detailed model that accurately predicts the behavior of the watch in the future (including subtle effects like slowdown with age and other inaccuracies). So, which one would be right? Perhaps none of them. One day the watch could do something rare that nobody has ever seen it do before and suddenly invalidate all of the models.

Without perfect data and without detailed knowledge of the very fundamentals of the Universe, all of our science is just approximate modelling and detailed guesswork (to some degree or other). With lots of data and careful reasoning, science can produce very detailed and reliable models of some things. But unusual observables that we have very limited access to can be very challenging to explain.

And because of that, science is still a very interesting endeavor!

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 5:25 pm
by BMAONE23
Didn't Einstein once say something like

There a two things that are infinite
The Universe
and human stupidity
and I'm not sure about the Universe

Unfortunately, as Humans, we often believe that we are correct in what we think we know
1500 years ago, the Earth was the center of the Universe
700 years ago, the Earth was flat
500 years ago, 6 stars moved in the sky
100 years ago, your skin would rip off if you traveled faster than 35 mph
60 years ago, the best way to survive an atomic attack was to hide under your desk
3 years ago, the solar system contained 9 planets

Wisdom changes and we are foolsih to proclaim anything absolute.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 5:45 pm
by geckzilla
BMAONE23 wrote:Didn't Einstein once say something like

There a two things that are infinite
The Universe
and human stupidity
and I'm not sure about the Universe
There are a lot of quotes attributed to Einstein that are either taken out of context or misattributed to him entirely. Here is some useful information regarding this quote specifically.
http://quoteinvestigator.com/2010/05/04 ... -einstein/

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 5:47 pm
by Chris Peterson
BMAONE23 wrote:Unfortunately, as Humans, we often believe that we are correct in what we think we know
1500 years ago, the Earth was the center of the Universe
700 years ago, the Earth was flat
500 years ago, 6 stars moved in the sky
100 years ago, your skin would rip off if you traveled faster than 35 mph
60 years ago, the best way to survive an atomic attack was to hide under your desk
3 years ago, the solar system contained 9 planets
In my opinion, this sort of construct is a fallacy. It emphasizes what we didn't know, and not what we do know. In fact, the reason we stopped believing many of those things is because we gained knowledge. Particularly in the last few hundred years, with the rise of rational approaches to learning about nature (broadly, the "scientific method"), our knowledge has grown vastly. One of the things this way of thinking has brought us is a way of assessing the quality of our knowledge. I would argue that the things we think we know with great certainty today are unlikely to be wrong. There are other things that we think we understand, and which usefully describe our observations, but which few scientists would argue are certain to be true (for instance, the Big Bang cosmology). That's a very different way of looking at thing than in the past, where belief in ideas was much more absolute.

I think hackerspiff is very much on the mark with his assessment of science, to which I'd only add, our knowledge always increases, and with time we come always closer to the truth (recognizing that the "truth" may never be more than a near-perfect model). We know more about how the Universe works today than we did in the past, and I think that future critics will find it much harder to construct lists of things we now believe but which in the future will seem silly.

A few observations about your specific list are in order:

-It was never held by educated people that the Earth was flat.
-The six star-like objects that moved in the sky have been recognized as something other than stars for well over 500 years, which is why the designation "planet" came into being.
-It was never held by educated people that your skin would rip off at greater than 35 mph.
-Hiding under your desk in a nuclear attack was a political instruction, not a scientific one.
-Three years ago there were nine planets in the Solar System; all that changed was a definition used by a small number of people. No knowledge changed, nothing was "wrong" with the previous usage.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 7:22 pm
by BMAONE23
-It was never held by educated people that the Earth was flat.
-The six star-like objects that moved in the sky have been recognized as something other than stars for well over 500 years, which is why the designation "planet" came into being.
-It was never held by educated people that your skin would rip off at greater than 35 mph.
-Hiding under your desk in a nuclear attack was a political instruction, not a scientific one.
-Three years ago there were nine planets in the Solar System; all that changed was a definition used by a small number of people. No knowledge changed, nothing was "wrong" with the previous usage.
The key word in your replies is "Educated"
I probably should have phrased the statements as "to the masses" Because the statement attributed to Einstein was made in reference to the uneducated masses.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 9:11 pm
by bystander
Every generation of humans believed it had all the answers it needed, except for a few mysteries they assumed would be solved at any moment. And they all believed their ancestors were simplistic and deluded. What are the odds that you are the first generation of humans who will understand reality? — Scott Adams

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 9:44 pm
by geckzilla
Well put, Mr. Adams...

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 9:48 pm
by Chris Peterson
bystander wrote:Every generation of humans believed it had all the answers it needed, except for a few mysteries they assumed would be solved at any moment. And they all believed their ancestors were simplistic and deluded. What are the odds that you are the first generation of humans who will understand reality? — Scott Adams
I think he is wrong on two counts. First, I don't think every generation of humans believed it had all the answers (although perhaps some believed they had all the answers they thought they needed). Second, I don't think we are a generation of humans who expect to understand reality.

Throughout history, there have been cultures that cultivated scientists and philosophers who tried to answer important questions about nature. The fact that they were asking questions at all means they didn't think they had the answers. Today, we not only ask the questions, but place probabilities on the answers. Nothing is taken as absolutely certain.

Of course, I'm again talking about the educated segment of society, which may or may not be a majority (usually not). The beliefs of the uneducated, and of those duped by mythology, religion, and dogma are a different matter, and may define entire cultures even if a few members know better.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 10:34 pm
by geckzilla
I don't want to sound presumptuous, Chris, but you're making yourself sound like you don't get out much. ;)

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Tue Mar 29, 2011 11:10 pm
by Beyond
GREAT Scott! -- "REALITY"-- Maybe one day it will come out from what It's been hiding behind all this time and say - "Hello".
It would most likely be the best APOD Topic of ALL time. I wonder what the picture would look like??
I'm pretty sure It's number would be more than 42. :mrgreen:

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Apr 01, 2011 12:48 am
by neufer
garry wrote:
A square shape is not found in nature.
Image

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Nov 04, 2011 3:08 am
by neufer
http://messenger.jhuapl.edu/gallery/sciencePhotos/image.php?gallery_id=2&image_id=685 wrote:

Of Interest: The surface in this [Mercury MESSENGER] image is located near the center of the large Caloris basin. The linear troughs radiating from the lower left corner are part of Pantheon Fossae, while numerous other fractures can be seen crisscrossing the basin's floor. MESSENGER's orbital images are revealing a complicated set of tectonic features within Caloris basin, many more than previously mapped.
garry wrote:
A square shape is not found in nature.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Nov 04, 2011 2:12 pm
by Rouzbeh
That Square nebula is probably one of the most unique I've ever seen

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Dec 26, 2014 12:07 pm
by cljohnston108
This was posted on io9 just now...

Why Is This Nebula So Perfectly Symmetrical? | io9

Intrigued, I went looking for more information... except there is NO further information!

NO other pictures (like from Hubble) and NO follow-up articles, etc. NO mention of this thing past mid-April, 2007, except for this APOD posting (of the same image) right here.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Dec 26, 2014 3:14 pm
by Chris Peterson
cljohnston108 wrote:This was posted on io9 just now...

Why Is This Nebula So Perfectly Symmetrical? | io9

Intrigued, I went looking for more information... except there is NO further information!

NO other pictures (like from Hubble) and NO follow-up articles, etc. NO mention of this thing past mid-April, 2007, except for this APOD posting (of the same image) right here.
Symmetry seems like something we should expect. A more interesting question is why so many similar objects are strikingly unsymmetrical.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Dec 26, 2014 3:39 pm
by geckzilla
Chris Peterson wrote:
cljohnston108 wrote:This was posted on io9 just now...

Why Is This Nebula So Perfectly Symmetrical? | io9

Intrigued, I went looking for more information... except there is NO further information!

NO other pictures (like from Hubble) and NO follow-up articles, etc. NO mention of this thing past mid-April, 2007, except for this APOD posting (of the same image) right here.
Symmetry seems like something we should expect. A more interesting question is why so many similar objects are strikingly unsymmetrical.
I disagree somewhat, I think. Let me ask you first what you mean by "many similar objects" before I do so, though. If you mean supernova remnants, I agree, they are pretty disorganized. If planetary nebulas, then those do quite often exhibit some kind of symmetry even if it's fallen apart somewhat over tens of thousands of years.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Dec 26, 2014 3:52 pm
by Chris Peterson
geckzilla wrote:
Chris Peterson wrote:Symmetry seems like something we should expect. A more interesting question is why so many similar objects are strikingly unsymmetrical.
I disagree somewhat, I think. Let me ask you first what you mean by "many similar objects" before I do so, though. If you mean supernova remnants, I agree, they are pretty disorganized. If planetary nebulas, then those do quite often exhibit some kind of symmetry even if it's fallen apart somewhat over tens of thousands of years.
I mean objects that result from explosive events. I'm certainly not saying that many aren't symmetrical! Just that it is the lack of symmetry in some cases that seems most interesting to me. And I'm talking about young objects- I certainly understand the mechanisms by which symmetry fails over time.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Dec 26, 2014 3:54 pm
by geckzilla
Chris Peterson wrote:I mean objects that result from explosive events. I'm certainly not saying that many aren't symmetrical! Just that it is the lack of symmetry in some cases that seems most interesting to me. And I'm talking about young objects- I certainly understand the mechanisms by which symmetry fails over time.
Oh, I misunderstood you to mean that few of them are symmetrical rather than what you apparently meant is that more than you'd expect are asymmetrical. Hey, show me an example of a young, asymmetrical object.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Dec 26, 2014 4:01 pm
by Chris Peterson
geckzilla wrote:Oh, I misunderstood you to mean that few of them are symmetrical rather than what you apparently meant is that more than you'd expect are asymmetrical. Hey, show me an example of a young, asymmetrical object.
I'm too lazy to track one down just now. Next time I notice one I'll point it out. But I'll bet that you could find one pretty quickly. Seems like you spend a lot of time seeking out interesting objects from image sets.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Dec 26, 2014 4:08 pm
by geckzilla
Chris Peterson wrote:
geckzilla wrote:Oh, I misunderstood you to mean that few of them are symmetrical rather than what you apparently meant is that more than you'd expect are asymmetrical. Hey, show me an example of a young, asymmetrical object.
I'm too lazy to track one down just now. Next time I notice one I'll point it out. But I'll bet that you could find one pretty quickly. Seems like you spend a lot of time seeking out interesting objects from image sets.
I was looking over them during these posts and didn't find any. There are some that are more nicely symmetrical and others that are more sloppy looking but there are none that I know of that are totally devoid of symmetry. Frosty Leo is a good example of a sloppy one and there are a couple of IRAS objects closely resembling it but it's still no problem seeing a history of symmetrical polar outbursts in any of them. Maybe the Calabash nebula is the most exceptional one. It's easily symmetrical but one lobe is significantly stunted compared to the other.

Re: APOD: MWC 922: The Red Square Nebula (2011 Mar 23)

Posted: Fri Dec 26, 2014 4:19 pm
by Chris Peterson
geckzilla wrote:I was looking over them during these posts and didn't find any. There are some that are more nicely symmetrical and others that are more sloppy looking but there are none that I know of that are totally devoid of symmetry.
Again, you might be overreading my initial comment. I'm not talking about totally asymmetric objects (although that would be fascinating), just objects that have obviously significant asymmetries, like paired lobes of very different sizes, or jets in just one direction. Since all of these objects originated in (presumably) highly symmetric bodies, the source of the asymmetry becomes very interesting.