APOD and General Astronomy Discussion Forum
https://asterisk.apod.com/
Rare, but found!garry wrote:A square shape is not found in nature.
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.What Is It wrote: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!
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.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
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.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
The key word in your replies is "Educated"-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.
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.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
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.
Symmetry seems like something we should expect. A more interesting question is why so many similar objects are strikingly unsymmetrical.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.
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.Chris Peterson wrote:Symmetry seems like something we should expect. A more interesting question is why so many similar objects are strikingly unsymmetrical.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.
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.geckzilla wrote: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.Chris Peterson wrote:Symmetry seems like something we should expect. A more interesting question is why so many similar objects are strikingly unsymmetrical.
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.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.
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.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 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.Chris Peterson wrote: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.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.
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.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.
