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Wild Card 004.1 “A Chaotic Discussion of Critical Thinking, Chaos, and Large Systems.”

Posted by Rick Shaffer   07/11/2004 07:00AM

Wild Card 004.1 “A Chaotic Discussion of Critical Thinking, Chaos, and Large Systems.”
I’ve decided to stop taking my medicine again, so you can expect this edition to be a bit schizophrenic. We’ll start off with a modest rant about the lack of critical thinking many of us, including me, are demonstrating lately.

The image at right was sent to me by a fellow amateur. It was billed as “one of the last pics of the Earth taken by our brave astronauts aboard “Columbia” just before it crashed”. Putting modesty aside, where I must admit it stays most of the time, I realized that this pic couldn’t be genuine.

Here’s a probably-not-complete list of the reasons it’s gotta be bogus: (1) The view stretches from N. Africa to Greenland, a span that can’t be seen from low Earth orbit. (LEO), (2) Greenland can’t be seen from the shuttle in its usual LEO. (3) The terminator is running at nearly a N-S orientation, despite the fact that the final mission of Columbia occurred in late Jan2003. (4) The BOTTOM OF THE OCEAN appears to be visible in this pic! (5) Even though it was supposedly taken in Winter, there’s not a cloud in the sky! (6) Moe was the smartest Stooge. (Just wanted to see if you were actually paying attention.) (7) Despite the fact that it’s still in sunlight, Paris is lit up like the sun’s already set. (It’s the “City of Light”, but this strains credulity!) (8) Jean-Luc Picard was the best captain of the “Enterprise”. (Still paying attention?) (9) The terminator is too well-defined for this to be an actual picture. (There's a "governor of CA" joke here, but I can't quite get it to work!) (10) The “real” Earth doesn’t come with a color-code to denote altitude above sea level. (11) To the best of my knowledge, the Sahara Desert doesn’t glow at night. (12) You get the idea…..

The person who created this image probably used something like John Walker’s free software, “Home Planet” or one of the products of the USGS mapping sites. It’s an interesting exercise, but it surely didn’t originate aboard “Columbia”. And shame on the hoaxer for trying to get some “image-hacker street-cred” out of that tragic event!

But shame on any of us whose “BS filter” was set so “wide open” that we looked at that pic and didn’t see the obvious defects.

When we watch a SciFi TV show, it’s all right to suspend disbelief. After all, the “Fi” in “SciFi” does stand for the word “fiction”. And nobody worries too much about the outcome of the latest match on TV wrestling shows. We know it’s just entertainment, not a “real” contest.

But we’re not thinking critically as much as we should. Here are a few examples:

1. I live in Sedona, AZ, the ancient-wise-person channeling, crystal-crunching, vortex-visiting, swami-worshipping (when we’re not worshipping the almighty $) capital of the World. So this shouldn’t surprise me. A friend of mine who lives in the neighborhood is dead-bang sure we never sent anyone to the Moon. This guy runs his own business, and I’m pretty sure he knows the location of every nickel of capital he has, but he truly believes all those guys were just “bouncing around on a sound stage” instead of risking their lives actually exploring the Moon in space suits. And a lot of others believe the same thing.

2. In 1997, a “spacecraft flying in formation” with Comet Hale-Bopp was “discovered” in an image by a misguided newbie to amateur astronomy. It made a lot of news. Shortly thereafter, I got a call from a representative of a late-night radio talk show program. My name had been given to them by someone who had seen a talk I’d given to my local club, and they wanted me to appear on their show. (I seem to remember that it was something like the “Al Bong Show”, but that detail is hazy. But we'll go with that name.) A time when I could talk off the air with the host was set up, and the phone rang at the appointed time. It was, indeed, “Al Bong” himself.

“Well, let’s get right to it, Rick.” he said. “What would you say if I asked you about the spacecraft that’s flying along with the comet?”

“Hmmm. Well, Al, let me ask YOU a question. If you were the captain of a really expensive spacecraft, and you wished to hide it from the view of the inhabitants of a planet in the system you were exploring, would you fly alongside a big, bright, gaudy comet that those same folks were probably studying rather intensely, or would you maybe park your spacecraft on the side of the Moon opposite the Earth, where the Earthlings couldn’t see it?”

“What’s your point?” asked the Great Man.

“My point is that, even if that guy could have imaged it, that “spacecraft” wouldn’t be THERE, right behind an object that’s putting out an amazing amount of dust, gravel, and gas!”

“Oh, well, couldn’t they use their shields?”

“I don’t know if ‘shields’ even exist, Al. I just know that the object the guy imaged was a bright star. He just made a newbie mistake with his star mapping software, and thought he’d imaged something that he hadn’t. It’s just a mistake.”

The the Great Man spoke: “Uh, Mr. Shaffer, I don’t think you’d be right for our show. But thanks for taking the time for me, though.” CLICK! (Oh, darn! Another golden opportunity missed!)

3. On one of the forums earlier this week, someone was claiming that a $59 ultra-wide-angle eyepiece was providing “almost as good a view” as a well-known “potato-masher” eyepiece that costs 10-times as much. It didn’t matter that the eyepiece was a prototype, or that the production eyepieces might or might not be as good. Nor did it matter that other eyepieces in the series didn’t perform as well. That statement is what will “stick out”. I suspect that many (too many?) of those eyepieces will be sold based on that post. I also suspect that quite a number of the folks who buy them will realize all too soon that they’re not nearly so good as they thought, once they take the rose-colored filter out of the barrel.

4. There’s a lively debate going on in one of the forums about the merits of the various achromatic, semi-apochromatic, and apochromatic refractors being imported from China. There seems to be a core of folks who believe that, due to some “miracle of Asian manufacturing”, a new telescope of extraordinarily-high quality will somehow be available at an extraordinarily low price. This belief is expressed over and over, despite the fact that the folks expressing that belief have not yet seen a single copy of the telescope!

I’d love it if such a telescope existed. I’d also love it if I could eat all the pizza and drink all the chocolate milk shakes I wanted with impunity. But, Heinlein said it best in his 60s novel “The Moon Is a Harsh Mistress”:

“TANSTAAFL” (“There ain't no such thing as a free lunch.”)

So, that telescope won’t likely exist, at least not at the quality or in the numbers claimed by the importer, and I’ll still have to watch my diet. Reality always has a way of being more real than fantasy.

5. Even veteran telescope designers occasionally don’t think as critically as they should. For example, in a recent forum post, a fellow member asked if a lens another member wanted ID-ed could be used as a transfer lens in his Schmidt Newtonian to erect the image. I answered (correctly) that it might be suitable as a transfer lens, but didn’t think critically about the problem, and failed to notice that the image would, indeed be right side up, but it would be reversed left-for-right because of the image reversal caused by the diagonal. (That yellow stuff you see dripping from my chin is egg.)

The above examples suggest that we all need to narrow the bandwidth of our “BS filters”. And, we need to keep a constant vigil on the knob that adjusts the bandwidth to ensure that it doesn’t get tweaked! And, BS is BS, even if it’s our own!

>>>>A Little More on Chaos, Large Systems, and the Fact That a Lotta Stuff is Buried on My Desk:

In “Wild Card 004”, I alluded to the fact that Chaos Mathematics seems to predict that it’s impossible to predict the future behavior of large systems for very far into the future. (And ain’t THAT a nicely-twisted sentence!) As fate (or whatever) would have it, there was a series of posts started by a guy named “Lucky” from Lithuania. Here’s what (actually Bob) wrote:

“I moved to Florida 33 years ago because I love to fish. And the successful fisher-person pays close attention to the ebb and flow of the ocean tides. The experienced boater would note that tidal flow is one of the most powerful forces of the sea.

OK astronomers if the water of the oceans is subject to gravitational tides - does the atmosphere of our earth, or any planet, exhibit a similar, periodic, tidal ebb and flow.

What say you?”

Several members replied, correctly, that the Moon essentially “pulls up” on the Earth as it proceeds in its orbit. (The number I’ve seen most often is 8-10”.) This, of course, puts stresses on the crust, which can contribute to earthquakes and vulcanism (which has nothing to do with "pointed ears"!). How much, we really don’t know. There was also a suggestion that, if the Moon can pull up on the solid part of the Earth it ought to be able to pull on the atmosphere, as well. The contention, here, is that gravity affects any particle that has mass, regardless of its state (solid, liquid, gas, or plasma). That’s true, as well.

[Here’s a little problem for you: We know that the average pressure at sea level here on Earth is 14.7-lbs-per-square-inch. If we assume that the Earth is a perfect sphere, how much does the Earth’s atmosphere weigh? (BTW, this is a problem I couldn’t solve in my senior year Physical Chemistry class in college. May you see the obvious that I missed!) Answer next week.]

Another member pointed out that the volcanoes on the Jovian satellite Io are caused by the fact that Io is internally heated by tidal forces. That’s correct, but it might deserve a bit more explanation:

Putting stress on something heats it. If you don’t believe that, put a 16-penny nail in a vise and bend it back and forth with a pair of heavy-duty pliers until it breaks. Then put you finger on it. You’ll likely jump back rather quickly, because the thing will be really hot! If you could do this to the nail in such a way that it couldn’t fail physically, you could get it to be dripping hot steel. (Please don’t try this at home!)

What happens with Io is that Jupiter is so massive, and Io orbits so close to Jupiter that there’s a fairly big difference between the force on the closest point on Io to Jupiter and the force on the farthest. (This difference in forces is what causes any tide.) If Io were much closer to Jupiter, that difference would be enough to literally tear it apart. But Io isn’t that close, so it just, essentially, “kneads” the satellite constantly, making it a hot, plastic body with a solid surface. Occasionally, some of the liquid interior of Io erupts, and sprays the surface. The hot material cools and replenishes the solid surface. Meanwhile, the bottom layer of the mantle melts into the liquid core, to be recycled, “ad volcanium”.

In very simple environments, the prediction of the tides is fairly easy. For example, the Atlantic Ocean has two tides each day, and so does the Pacific. But the tides are close to equal in the Atlantic, and not in the Pacific. The Caribbean Sea, however, has little tides, but the Gulf of Mexico only has one high tide each day. And, of course, the Mediterranean has no real tides. The key to understanding the tides is that, the more complex the system, the harder it is to make a model of it that will predict its future behavior. The Atlantic and Pacific are fairly simple systems, with few islands to affect the tides. But, the Caribbean and Gulf of Mexico do have a lot of islands to complicate things, so their tides aren’t as simple. BUT, the areas that define the transition between the simple Atlantic and the complex island regions have tides that are only partially predictable with mathematical models. Predicting tides for these regions has been as much art as science.

[Note that there are regions of the Mediterranean Sea where the tides are quite chaotic. One small bay in the Adriatic Sea has an oscillation of its tidal flow that sometimes occurs 14-TIMES each day! And, of course, the well-known tides in the Bay of Fundy in Nova Scotia, Canada are so powerful that the level of the water changes by as much as 40-FEET!]

If you think that dealing with something like the tides is difficult, try predicting the weather! Our weather is affected by so many variables that it is, as a system, only able to be modeled with any accuracy for a few days in the future. I’ve only had one course in meteorology, so I’ll not try to cover that subject, but I’d like to present a little vignette that I hope will illustrate just how complex is the relationship between our planet and it’s atmosphere:

Years ago, I was managing the acquisition of interstation timing data in the Deep Space Network. We were using Very Long Baseline Interferometry, a radio-Astronomy technique, to measure the difference in the time indicated by the master clocks at the three different complexes (Goldstone, Canberra, and Madrid). We needed those data because we were also doing VLBI-type navigation on the Voyager spacecraft.

One day I was having lunch with one of the guys who was responsible for doing the correlation (crunching of the numbers) of the data. He was complaining that the data were a bit noisier than usual. Fearing that there was a problem with what the folks in my area were doing, I asked for more info. He said, "Oh, sorry, Rick. There's nothing wrong with your data acquisition. It's just that there was a big storm in South America, and the winds from the West gave the Earth a little push on the Andes Mountains. We're having trouble modeling that, so the solutions we're getting are a little noisier than usual."!

I don’t know if that effect ever got modeled well, but I suggest that it’s just one of many. And it would need to be modeled, because, when the Earth sped up due to winds from the storm pushing on the Andes, energy was taken out of the weather system and stored in the rotational inertia of the Earth.

If we were to try to model the weather, would we need to account for each mountain range, each mountain? Of course, Chaos Mathematics saves us the trouble. It says that it doesn’t matter how well we model the Earth Weather System. There are just too many variables for us to be able to accurately predict the behavior of this system.

A few years ago, I gave a talk to an astronomy club about Chaos and how it affects our lives here on Earth. During the question and answer period, a grandmotherly woman stood up and asked, “Mr. Shaffer, can you think of no way we could make a model we could use to predict the weather?” (I later was told that Edna, the questioner, prided herself on asking the most “interesting” questions of the club’s speakers.)

I thought for a moment, and replied, “Well, yes. Let’s say that we want to be able to predict the weather, or any other aspect of how our Universe behaves, for 30-days in advance. We’d just create a Universe just like ours, right down to the last detail. In other words, it would have the exact same “initial” conditions as our Universe. We’d just do one thing differently. We’d start it 30-days before the Big Bang occurred in “our” Universe. That way, anytime we wanted to know what would happen in our Universe in 30-days, we’d just look at the “control Universe”, and we'd know.

I was greeted by silence. Finally, someone asked, “Shouldn’t we just leave that to the Almighty?” I replied that I’d be happy to do that. Besides, the above scheme is MUCH too involved with the phrase “We’d just…”!

NEXT WEEK: "How to get an unobstructed telescope without having to spend a wheel-barrow-full of money."

RICK SHAFFER is an astronomer, writer, designer/builder of telescopes, and teacher who lives and works in Sedona, AZ. He’s dead sure that Chaos Mathematics accurately describes the behavior of large systems. All he has to do to convince himself of that is to look at his desk!