Saturday, December 23, 2006

Holiday Hiatus

There is a remarkable breakdown of taste and intelligence at Christmastime. Mature, responsible grown men wear neckties made of holly leaves and drink alcoholic beverages with raw egg yolks and cottage cheese in them. ~P.J. O'Rourke

Since my employers thoughtfully give me some time off at Christmas and New Year's, just long enough for the equipment to break down while I'm enjoying new toys, football, and food, Explorations will take some time off as well. In the meantime, if you must have a fix of weblog, peruse the archives. I'm sure you'll find something in there of interest.

Oh, and we can all be thankful that the shuttle returned safely before a) it ran out of power, and b) the year changed (since its computers can't automatically switch over to a new year).

Have a very Merry Christmas and a Happy and Safe New Year.

Thursday, December 21, 2006

Traveler's Tales

When you know a thing, to hold that you know it; and when you do not know a thing, to allow that you do not know it—that is knowledge. ~Confucius

Scientists had high hopes for the Stardust mission, and, so far, they aren't being disappointed.

Stardust spent five years catching up to comet Wild 2 (pronounced Vilt, for those of you who wish to be precise), caught a myriad of tiny particles in its aerogel-filled collectors, and high-tailed it back to Earth, landing in the Utah wilderness softly (unlike its friend Genesis, who pancaked in the desert). After an exciting hour or two of searching, the team recovered Stardust, and the scientists have been going slightly crazy ever since.

There are so many impacts in the aerogels that the public has been enlisted to search through the collector images to try to identify promising particles. Stardust will be yielding information for years to come.

It has already served up some treats. One particle has been discovered that is apparently not from our solar system. This is determined by the oxygen isotope content. This tiny bit has 150% more of the heavy oxygen isotope than it should have. Comet Wild seems to have collected some detritus from outside our immediate neighborhood.

Most of the samples studied so far would indicated that Wild, like many such objects, formed out in the Kuiper belt and has only lately wandered into the inner part of the solar system. At least, that should be the case, but one of the samples returned isn't from the icy reaches beyond Pluto. It seems that it is something called osbornite, which forms in temperatures of 3000 degrees Kelvin.

That's hot, and how something heated like that got into the comet is a mystery. Scientists can only speculate that the nebula in which the Sun and planets formed was more active than previously imagined. Then there's the organic material.

"We didn't expect any organics to survive" from the impact and heat during the collection process, said Livermore researcher Sasa Bajt (see Resources for the Science Daily article). "But we found a rich variety of organics that were both oxygen-rich and nitrogen rich compared to organics previously found in meteorites.” Finding organic materials lends considerable credence to the theory held by some that life on Earth was “seeded” from extraterrestrial sources.

Even the idea of what a comet is has come under scrutiny. For years, the general theory of cometary makeup was best described as the “dirty snowball” scenario. All comets were formed away out there somewhere out of gases and light materials left over from the creation of the Sun and planets. Away out there was where they stayed until perturbed by something or other, at which point they would come into the inner planetary area, outgassing geysers of some sort of melting matter as they neared the Sun. The biggest question was whether they were relatively solid or whether they were just jumbles of rubble loosely held together.

Now, it seems that every time we get near a comet, we find out something different. Wild 2 has been both very hot and very cold. Tempel I, target of Deep Impact had its own surprises.

Deep Impact was a remarkably ambitious attempt to send a probe (if one can call something the size of a washing machine a “probe”) crashing into a comet to study the ejecta and possibly see into the comet. The Deep Impact team was both delighted and disappointed by the result. They were elated that they actually hit the bloody thing. After all, you've got Deep Impact hurtling headlong toward a large fast object; at full tilt, you push off a probe which has its own navigation system and swing the main satellite out and around so it won't hit Tempel. By some miracle, the probe actually gets where it's supposed to go, and the result is a spectacular outburst of light.

That was also the bad part. As Deep Impact whizzed by, it couldn't see into the comet at all because the glare was terrific. But, the Swift X-Ray telescope saw something, and that was odd, because it wasn't supposed to. No one is quite sure yet why there was an outpouring of X-rays from Tempel I and why it should have lasted for 12 days. In fact, optical telescopes only saw optical flaring for about 5 days, so the mystery of what was going on in the remaining 7 is perplexing.

Amazingly for the amount of vaporization, it also turns out that Tempel is only 6% water, with the rest being a rather fragile agglomeration of dust. So where did the X-rays come from?

One of the Deep Impact scientists put it best, soon after the successful probe impact. At the time, we had taken a close look at three comets, Halley, Wild (photographic returns; the samples were still in route), and now Tempel. Here we were, expecting comets to be pretty similar in makeup, yet all three were very different. It seems like the more we were learning about comets, the less we knew. It also turns out that we know a lot less about the early solar system than we thought.

Carl Sagan once talked of the Voyager satellites sending back 'traveler's tales.” Apparently, Stardust, Deep Impact, and even Genesis (whose sample collectors are still being diligently cleaned) have new tales to tell us.

We're listening.

Resources:
Stardust's Comet Clues Reveal Early Solar System
"Deep Impact" Comet Spewed Tons of Water, Study Finds
Comet grain confirms early solar system mixed it up
Space Probe Brought Real Stardust Back to Earth
Comet Particles Tell New Story About Birth Of Solar System

Tuesday, December 19, 2006

Hits and Myths

Legend: A lie that has attained the dignity of age. ~ Laurence J. Peter

We do love our myths. The success of "Mythbusters" on the Discovery Channel is tribute to our love of legends (and explosions) both great and small. In addition, the endless programs about UFO's, legendary creatures, and prophecies show that many people just can't get enough of this sort of thing.

Take the Loch Ness monster. People have been seeing this thing since there were people to see it. They have produced pictures, have sworn on a stack of Bibles to seeing it, and have funded lengthy research efforts to find the illusive Nessie. What we have to show for it are some grainy films, some dubious photographs (include one outright forgery), and no sea monsters.

We should expect no more than that. Loch Ness doesn't have enough fish in it to support a large sturgeon population, much less a family of pleisiosaurs swimming around for hundreds of years. But, if one was to assume that somehow Nessie and her mates could eke out a living, there would have to be enough of them to ensure that they could reproduce in sufficient numbers to maintain a population of them in the lake. If you have so many of something so large swimming in an enclosed lake, a sonar survey would have revealed them. One such survey, which featured boats strung completely across the loch, came up completely empty.

Yet people want to believe so much that they can be fooled by the so-called “surgeon's photo.” The photo, taken by someone who was angry at a newspaper that had not paid for his search efforts at Loch Ness, was fronted by Robert Wilson, a surgeon, to give it legitimacy. Long held to be absolute proof of the existence of Nessie, some years ago it was revealed, by Wilson's son, I believe, that in actual fact the photo was of a fake “Nessie” head attached to a toy submarine.

Our oceans are full of exotic and wonderful creatures, like the giant squid, yet people prefer to believe in a prehistoric creature lurking in a Scottish loch.

Then there's the matter of UFO's. No one is more intrigued by the possibilities of intelligent life on other planets than me. I've speculated about since I was old enough to realize that there were other planets. But the bulk of the UFO believers are wrapped up in conspiracies (what would they do without Area 51?), abductions, and metaphysics that they seem to have a weak grip on the realities of the situation.

J. Allen Hynek was the official de-bunker for the U.S. Air Force for years. He left after some time, not because he thought there some some deep governmental conspiracy to hide the “facts” about alien visits to Earth, but because he felt the Air Force was forcing explanations on observations that were truly unidentified. His stand was that there were indeed some things showing up in the sky that we didn't understand, and he wanted to be able to research them. As far as he was concerned, calling every strange sighting a weather balloon was just as bad as calling it a flying saucer.

In fact, Dr. Hynek continued his debunking of faked photographs and hokey abduction stories for years after his retirement, all the while trying to get people interested in investigating more mundane but completely unexplained sightings. He never really got anywhere, but he was popular amongst the UFO set, despite exposing some of their cherished “evidence” as fakes or erroneous interpretations.

The alien abductions always have rankled me. If we visited a planet and found intelligent life on it, would we:
  • a) Spend time observing the planet, attempting to learn how to communicate with the beings?
  • b) Make an immediate attempt to contact them using mathematical patterns?
  • c) Sneak down in the middle of the night, find a couple of drunken yokels, take them for a ride around their solar system, poke them with needles, then return them to the swamp where we found them?
To most UFO enthusiasts, the answer is most definitely c).

A co-worker and I were discussing this the other day, when he, a born and bred Alabamian, offered his opinion on why the abduction-of-drunk-rednecks theory is hokum.

“Listen,” he said, “if some good ole boy is stomping through the woods at night and sees a little green man coming at him, his first thought is going to be, 'I'm-a goin' to shoot that l'i'l green feller. He'll look good on the wall next to my buck and big bass mounts.” And blammo! There'd be one less E.T. left to phone home.

It's strange really how humans hold on to the ideas of the paranormal, legendary creatures, and flying saucers, among other myths. Much of this fascination has to do, I think, for the desire for something beyond the routine word we think we understand so well. People believe in ghosts because it gives them comfort about what happens after death. We like the idea of monsters in the oceans the same way we like dinosaurs; these are monstrous creatures that generate a sense of awe. And we love (and fear) aliens for a variety of reasons, many of which have to do with the idea of finding someone with greater wisdom than we have because they are so much more advanced.

Of course, if they're so advanced, how come they find bayou drunks so fascinating?

What's really ironic about this is that the universe around us is so much more fascinating than most people realize. As Sir Arthur Eddington once said, “Not only is the universe stranger than we imagine, it is stranger than we can imagine.” At the time, Sir Arthur may have been motivated by Edwin Hubble's findings, Einstein's theories, or the blossoming science of quantum mechanics. All of those events were jarring us out of a comfortable parochial sense of complacency, with the realization that not only did we not know everything about our surroundings, but we actually didn't know very much at all.

The average person, though, takes much of this scientific “stuff” for granted. They don't see the challenge of isolating a Higgs boson as all that interesting, while a huge sea monster floating around in Loch Ness is amazing. There's also a little rebellion at work here. Our teachers and the “experts” (whoever they are) are forever telling us what's what. We like seeing their balloons punctured. Of course, balloons are punctured all the time, but the argument over the expansion rate of the universe seems so abstract compared to the possibility that a spaceship set down last week in Biloxi.

There's nothing wrong with keeping an open mind toward myths. In fact, keeping an open mind is what discovery is all about. Investigating the strange has often led to very real discoveries. But the danger is in spending inordinate amounts of time and resources on those myths, as well as a willingness to discard facts in favor of unsubstantiated evidence.

So, keep an open mind toward the mythical, but never close your mind to reality.

Thursday, December 14, 2006

Of Curses and Kings

“You scoundrel, you have wronged me,” hissed the philosopher. “May you live forever!” ~ Ambrose Bierce

Curses

I swear that more Roman artifacts are found in England than in Rome and greater Italy. A recent find is one of those homely little items that connects us with the people of the past, not just the events. In Leicester, England, a “curse tablet” has been found. This is not to be confused with a letter full of curses, which I documented some time ago. As you may recall, one of the letters involved a woman who was scolding someone over a debt. The language was strong enough that the team that discovered it did not publicly release the complete translation for fear of offending the sensibilities of the general public.

As I said at the time, that's such a disappointment because cursing is in such a rut these days that we could use some imaginative foul language.

The curse tablet, on the other hand, has been completely translated. It said:
To the god Maglus, I give the wrongdoer who stole the cloak of Servandus. Silvester, Roimandus that he destroy him before the ninth day, the person who stole the cloak of Servandus.
This supplication is followed by a list of 18 or 19 suspects. Evidently Servandus wasn't into doing extensive detective work; he also wasn't very popular if there was a platoon of people who would gleefully walk off with his cloak.

You've got to admire the simplicity of this curse. “Hey, Maglus, kill the creep who copped my wrap.” Nothing very flowery about Servandus.

This find is the sort of thing that reminds us that people have been people a long time. Some Roman postcards were found some years ago in England. One asked someone to send socks (very handy apparel for a Roman in the chilly north of Britain); another invited a friend to a party. It's one thing to talk of Julius Caesar and Hadrian, mighty leaders of empire whose minions ranged across the world. It's another thing to find that one of those minions wrote home for socks. I can relate to the guy writing about the socks far more readily than I can to Hadrian.

Curse tablets, according to the article, were the sort of thing that ordinary folks used, the wealthy being able to call on the local priesthood (with an appropriate donation) to personally appeal to the gods in their favor. For someone in the working classes, like Servandus, the curse tablet was his main method of appealing to the gods for help. For a working man, the loss of a cloak was a serious loss. No wonder Servandus wanted blood.

Servandus' curse turns out to be more informative than one might expect. His role call of suspects includes Roman and Celtic names, giving archaeologists an idea about the makeup of the population in Leicester 1700 years ago. Many people have an image of the Romans marching into Britain, taking the all the Celts prisoner and sending them back to Rome as slaves. While this happened at times, particularly when local groups rebelled against the occupation, over time the Celts and Romans came to live together, with the locals benefiting from Roman civilization. When the Romans left, the Celts, in many cases, simply took over many of the cities, some of which are major centers today.

But my mind keeps drifting back to Servandus. I wonder if his curse got any action. Probably not, which leads us to wonder if he composed a new one with more names on it. I guess it depends on how many people Servandus thought disliked him.

Closing the Tut Case

A report was delivered at the annual meeting of the Radiological Society of North America that made official the results of a CT scan performed on King Tutankhamen. I am presuming this report was based on the scans taken some months ago in Egypt under the watchful eye of Zahi Hawass. Mr. Hawass was determined to try to find the actual cause of death of the Boy King once and for all.

It has been very popular over the years to ascribe Tut's demise to the machinations of trusted associates or even his wife. The Discovery Axis even enlisted a couple of private eyes to ride back and forth in a jeep in Egypt (or at least it looked like Egypt) for a couple of hours concocting a theory of how Tut was done in. They rehashed a bunch of old canards, finally coming up with a plot by Ay to bash Tut in the head so he could take over.

Sorry, guys. It just didn't happen that way. The simple fact was that Tut's skull never clearly showed the kind of damage a whack on the skull would produce. The CT scan verified that any bone fragments and minor damage to Tut's head came most likely came from the embalming process. Other breaks in his bones most likely came from his brute-force removal from the resins hardened in his coffin by Howard Carter and his associates. The same could not be said of his legs.

It seems that Tut suffered a grievous fracture to his leg. That the fracture occurred before death is certain as embalming resins covered the margins of the break, something that would indicate a compound fracture that broke the skin. People often died in the past from serious breaks. Infection would set in, which could lead to pneumonia, gangrene, or organ failure, and it could happen quickly.

One scenario has Tut being thrown from a chariot, perhaps while hunting. His tomb shows pictures of him riding his chariot in hunts and in battle, although the latter is less likely. Had Tut suffered such an injury, his likelihood of survival would not have been high.
It's entirely possible he died well away from his capitol. In that case, the heat of Egypt would have led to rapid degradation of the corpse, which might well explain the hurried burial. It may even explain why so much resin was poured into the coffin, an attempt, perhaps, to keep the body intact for the afterlife. Or its possible that the embalmers simply did a lousy job. Not all mummifications are equally successful.

Of course, there are those who will still search for conspiracies, no matter how much evidence is presented to the contrary. But, given the results of this scan, it would appear that the Tut murder case should be closed with a verdict of accidental death.

And I'll bet you thought I was going to tie up "curse tablets" with the "curse" of Tutankhamen. Fooled you, didn't I?

Tuesday, December 12, 2006

Ancient Smarts

Genius defies all anticipation. ~ Henri Bergson

One of the hallmarks of modern civilization is a remarkable smugness because of our technological advancement. For decades, the conventional wisdom was that the ancients were clever enough, but the real genius of mankind was to be found in the modern age. Over the last twenty years or so, we had to come to grips with the fact that early civilizations were a damn sight more advanced than we've credited them.

We have found that many of Da Vinci's clever designs actually work. Ironically, when we have trouble making them work, it's because our modern engineers try to “improve” them; when we follow Leonardo faithfully, the results are often remarkable. The more we investigate the engineering of the Romans, the more impressed we become with the sophistication and organization with which they were able to work.

And then there's the lump of bronze found off the island of Antikythera.

The Antikythera Mechanism, or, as it's familiarly known, the Antikytherum, was found in 1902 by sponge divers who were exploring a wreck. It was a lump of corroded bronze that was first thought to be part of a statue, but a closer examination showed that there was more to this lump than first met the eye.

There were gears, gears with v-shaped teeth. And that was totally unexpected.

The Antikythera Mechanism was dated to around 150 BC. There were known to be geared mechanisms dating to that time, but all of them had square gear teeth, which are easier to make. In fact, there were those who felt that there was not sufficient technology available at the time to make precise v-toothed gears. Yet here was a device that clearly had them. Moreover, no one had any idea what the mechanism did.

Since 1902, then, people have been using ever-improving x-ray techniques and scanning methodologies to examine the device. For years, all they've learned is that it's even more complex than originally thought. Writing was found on some of the parts which hinted at possible explanations. More gears were discovered. Finally, enough information was available to take a shot at building one.

Michael Wright was one of those who took the shot, demonstrating that with sufficient time, patience, and skill, the gears could be manufactured with the precision seen in the actual device. When he was done, he was sure he knew what it was: A planetarium.

According to Mr. Wright, the Antikytherum could show the positions of the five known planets, but that wasn't a sure thing, because not all the gears in the original mechanism were available. He had to make assumptions about connecting gears. Now a new analysis has come up with another view.

An Anglo-Greek team, using the latest scanning techniques, has reported that the Antikythera Mechanism was an eclipse calculator. But even they are hedging their bets, because there is writing on the device that says “Mercury” and “Venus”, so at least two planets were being followed, perhaps to study their retrograde motion. The presence of these two planets gives Mr. Wright hope that his interpretation may still be part of the device's use.

So, in 150 BC, we have an analog computer being made to calculate eclipses and possibly planetary positions, a mere 2000 years before any such tool was available to the modern world. Not bad for a bunch of philosophers.

But, if you want to go back, say 5000 years, you'll find something that is almost as amazing as the Antikytherum. Michael Barsoum of Drexel University, and a native of Egypt, has shown that the great pyramids at Giza still have surprises to spring on us. It seems that the ancient Egyptians were not only great engineers and planners, they were pretty fair materials engineers and chemists. It seems that some of the key elements of the pyramids were concrete blocks, not solid limestone. Particularly, the inner and outer casing and the upper blocks were cast in place using a limestone concrete.

That will dent some cherished beliefs of those who have theorized about the construction of these monuments. If the Egyptians were able to cast blocks in place, then some of the problems concerning the ramps needed to haul blocks up to the top of the structures would no longer be so troubling.

There's plenty of evidence to suggest the presence of ramps used in building the pyramids, but how the highest points of the pyramids were reached was always unclear. Did they have one immensely long ramp, or did they wind the ramp around the outside of the structures? Or did they use some sort of combination? Now it seems, according to Mr. Barsoum's peer-reviewed paper, that they found a better way.

Not only does this idea deal eliminate the need to transport large block to very high places, it also explains how the apparent precision of construction could be maintained. With the ability to cast blocks, cumulative imperfections could be overcome by pouring “corrective” blocks as needed or by using the cement to level areas as required.

But here's the really good part. The cement used by the Egyptians has lasted 5000 years. Modern Portland cement, the most commonly used variety today, has a life of 150 years. Now Portland has its own advantages, I'm sure, probably in strenght. But there are many applications where the cement of the pyramids would work as well. If a modern counterpart of the Egyptian compound was used today, it would reduce cement-related pollution (Portland cement releases carbon dioxide) by 90% and wildly outlast the current materials. Not bad for a bunch of ancient tomb-builders.

We have so much to learn.

Thursday, December 07, 2006

Debating Chixulub

A theory is better than its explanation ~ H. P. Woodward

Sixty-five million years ago, the dinosaurs shuffled off this mortal coil, and it's generally agreed on what dispatched them. The creatures appear to have been in decline, most likely due to climatic changes, possibly aggravated by huge lava eruptions that formed the Deccan Traps. Then, as if things weren't bad enough, a meteor came crashing down and finished them off.

Now, one version of the meteor's effects is that the entire planet caught fire, burning all the vegetation and all the dinosaurs who didn't have asbestos feathers, followed by a long-term winter caused by all the debris thrown into the air, which killed off all the vegetation (again) which caused the remaining dinosaurs to starve to death. This is the “dumb version” model. I've written before about this extreme description and how silly it is.

A more reasonable explanation is that the dinosaurs, as said were in decline. A meteor whacks the planet, causing huge amounts of damage on the continent where it impacted. It further throws tons of debris into the air, probably generating a prolonged period of cold which would have depleted the vegetation stocks. This would have probably caused the remaining herbivores to bite the dust. With the plant-eaters gone, the meat-eaters would have been very hard up for food and would undoubtedly gone to that big Cretaceous Park in the sky.

Of course, it would be nice if there was a crater to find that dated to around the time of the dinosaurs' demise, but we've got a reasonably big planet which is geologically active and has around 75% of its surface hidden under water. Not finding a crater would not mean that there was no meteor. Even without the hole in the ground, it's clear some sort of intervention from outer space occurred, because in the geological record at the point at which the dinosaur fossils disappear (known as the K-T boundary), there is a thin, dark, iridium-rich layer, and iridium is not common on Earth. It's most likely source would be from a significant meteor impact.

Despite the odds, a few years ago a crater was found off the Yucatan peninsula that was created 65 million years ago. The crater, dubbed Chixulub, was formed by a huge rock and would have readily accounted for the iridium layer. Bingo, say the scientists. The “smoking gun” has been found.

Initially, theorists laid the bulk of the blame for the mass extinction on the Chixulub event. As time has gone on, the other factors mentioned above have been recognized as precursors that would have made an impact event all the more devastating to the dinosaurs. Generally with few exceptions, paleontologists seem to have accepted the scenario of climate change (probably influenced by the Deccan eruptions) punctuated by the Chixulub impact as ringing down the dinosaur epoch.

Then along comes Gerta Keller from Princeton. The article I mentioned above was partly inspired by a program on the Science Channel (I think it was) that was pushing Ms. Keller's theory, which, to cut to the chase, is that Chixulub was not the cause of the extinction event. After generating a fair amount of misinformation, the program revealed that Ms. Keller thought another meteor was responsible. Well, she's mulled it over a bit, and now she's decided that there were a number of meteors of which Chixulub was only the first, according to this. In addition, the Deccan traps played a part, and the actual killer meteor may have landed where the traps were.

Thus, since last spring, when she was on TV, she's added more meteors, but she still has as her main goal the discrediting of Chixulub as the cause. In fact, that seems to be the only reason for her research. It was what she set out to prove, and by golly, she found evidence, at least in her mind, that proves it. Unfortunately for Ms. Keller, others have evidence that says otherwise.

In the TV program, in my opinion, most of her “proofs” were reasonably refuted, so I was a bit surprised to see her releasing a paper so long after the original report of her theory. However, she evidently did some reworking and gathered additional data. Now someone else has gathered even more data.

A study lead by Ken MacLeod of the University of Missouri, Columbia, investigated more core samples, this time along the northeast coast of South America. You can read the article for the details, but, basically, they indicate no evidence of another impact beyond that of Chixulub.

Ms. Keller reacted by saying that the core samples must have been “rearranged” or have sections “missing.” She describes the results as “rather hyper-inflated.” In other words, her basic response is, “Is not! Is not!”

Essentially, that was her response to criticisms of her theory on the TV program, where she said those who disagreed simply had too much investment in the Chixulub theory to let it go. Rather than respond to the criticisms, she merely dismisses them as professional churlishness.
Which is pretty lame.

I can't say categorically that she's wrong because I don't have the expertise to evaluate the evidence myself. I will say that every refutation of her theory I've seen makes sense. Ms. Keller's responses sound weak by comparison. Much of the basis of her theory lies in analyzing sediments that were thrown up by the impact of the Chixulub meteor, which are a hodgepodge of layers folded up and over one another. And, frankly, it seems that she approached those sediments with the idea of discrediting existing theories, not with the attitude of investigating with an open mind.

Ms. Keller may be on to something, but I am always suspicious of grandiose announcements “disproving” accepted theories. The goal of science is discovery, not disproving things. Einstein did not set out to disprove Newton's view of gravity, rather he expanded on it. Darwin did not set out to disprove Biblical creation; he sought to understand how we and the other creatures of the planet got to be the way we are. In investigating the universe around us, scientists often replace old theories aside; it's what scientific investigation is all about. But setting out to invalidate a theory isn't impartial investigation. It's almost like trimming jigsaw puzzle pieces to fit where you want.

You'll still get a picture; it just won't make much sense.

Tuesday, December 05, 2006

Maybe There Aren't Any Planets

To study any subject scientifically one needs a detached attitude which is obviously harder when one's own interests or emotions are involved. ~George Orwell

I figured we wouldn't be hearing much on the subject of defining the term “planet” for some time, once the sound and fury of reaction to the IAU decision died down. Oh, there was a petition, and Owen Gingerich was going to have his own conference to create a definition, presumably based on the one he originally helped create for the IAU. Mr. Gingrich was very upset because he had chaired the committee charged with coming up with a draft definition, which was no great shakes, but at the International Astronomical Union (IAU) session to decide the final definition, a new proposal was put forth and voted in.

Just to catch you up, the original draft definition read like this: A planet is an object that has enough mass to be round, is in orbit around a star, and is itself not a star or a satellite of another planet. There were also sub-categories in the Gingerich proposal, including “plutons”, a term that was already taken by the Geology crowd. It also promoted Charon to a planet, which promised to be confusing at the very least.

The final “approved" definition ran this way: A planet must orbit the sun; it must be massive enough for its gravity to force it to take on a nearly round shape; and it must have cleared the neighborhood of its orbit of other objects. This verbiage was deemed to have dropped the planetary roll call to 8, although a technical reading of the “clearing the neighborhood” bit could have disqualified Earth and Jupiter, and possibly Mars and Neptune, as well.

I call that a problematic definition, only because I'm using polite words here.

After all the fuss, everything seems to have quieted down rather abruptly. The Gingerich conference hasn't generated any news that I've seen, so I'm not even sure it's going to happen. Meanwhile, the IAU meets again in 2009, when it's presumed they will take up the issue again to try to regain some sense of authority in astronomical matters.

Robert Roy Britt over at Space.com has written rather boldly that there will never be a solid astronomical definition of the term “planet.” I find that disquieting in some ways, but he may have a point. Basically, there's a lot of stuff wandering around in the universe. There are stars, comets, large round gaseous things that have never ignited that are called brown dwarfs or planets (based vaguely on size), rocky round things that are either called planets or moons (depending on what they orbit), smaller round rocky things called dwarf planets (currently), ice round things called ice dwarfs (currently), and lumpy littler things called variously asteroids, Kuiper Belt objects, near-Earth objects, or moons (depending on where they happen to be). As Geoff Marcy says in the article, “Categorizing a thing does not magically add insight.”

True as far as it goes, but categorizing things does force us to attempt to pin down the properties of that thing. That's where the definition of an object comes in. By putting something into the “comet” category, say, we pretty much identify it as a member of a class of things that have a lot of ice and appear to be fairly loosely put together, which put off tails as they approach the Sun because the ices begin to melt and spew out of the comet.

But even comets are problematic. We've had a close look at a few of these interesting things, including crashing a probe into one. One of the Deep Impact scientists put it baldly when he pointed out that, so far, no two comets have been the same. So even something as well-known as a comet is still an unknown quantity in many ways.

Do we need a new definition of comets? Probably not, but we might ultimately need some subdivisions, such as rocky comets, sandy comets, and ice-predominant comets.

So what's wrong with subdivisions of planets? Not a thing, as I pointed out in earlier articles (see links below). What's wrong is creating ill-defined boundaries that tell us nothing about the objects. Lumping Pluto and Ceres into the same group (dwarf planets) is like lumping a dump truck and a boat together. The truck and the boat are both “vehicles” that carry passengers and cargo, but you need a finer grading to actually be able to tell what the major properties of both are. For example, dump trucks don't float worth a darn. That's important if you're trying to decide which one to take to the lake.

That's what is wrong with the IAU's definition. What was wrong with Gingerich's approach was that the overall category of “planet” was that it danced around the question, creating all sorts of ill-defined subcategories that still didn't tell you what would float and what wouldn't.

The exotic objects we're finding orbiting distant stars are just adding to the confusion.

I'm not enough of a scientist to come up with a definitive answer to the question of describing what constitutes a planet or what subcategories make sense. I think, though, that somehow the subdivisions should “add up” to the whole. That is, things like dwarf planets, ice dwarf, asteroids, and Kuiper Belt objects have a place in the evolution of the Solar System. Any set of definitions should not only separate these and other objects into groups, but they should also show how they are interrelated. Nothing I've seen from Mr. Gingerich or the IAU or anyone else seems to address this.

It's too easy to fob off the problem by saying we'll never come up with a good definition or, worse, saying we don't need a good definition. Science is not about taking the easy way out. It's time for astronomers to get their heads on straight and deal with the issue.

To borrow from Bette Davis, Science ain't for sissies.

Some earlier explorations into the subject:
Devaluing Pluto
Dwarfing Pluto
Pluto-nium

Plutonics

Thursday, November 30, 2006

Pardon Me, My Tardis Is Double-Parked

I wasted time, and now doth time waste me. ~William Shakespeare, Richard III

John Cramer of the University of Washington thinks he can send information back in time using quantum entanglement and “spooky action at a distance.” Once again, we see that, if you want to do something weird, you only need to go into the quantum world.

Mr. Cramer is not attempting to send a particle back in time. Instead, using a complicated scheme of detection, he hopes to show that a one of a pair of entangled particles has sent its state back into time to alert its partner as to what the partner's state should be. The researchers are also looking for a “signal” of some sort that passes between the entangled particles so that one knows what is going on with the other, although the article doesn't describe how they intend to detect that signal.

Back in “Spooky Entanglement”, I talked about how two quantum particles, a couple of photons for instance, can be “entangled” so that disturbances affecting the state of one immediately affect the state of the other, even if they are separated by vast distances. This is what Einstein derisively called “spooky action at a distance.” The effect is real; it's even been used, as explained in my previous piece, to teleport a particle from one place to another.

To review briefly, if you measure a quantum particle you disrupt it. If you learn it's location, you can't accurately determine it's momentum, for instance. A photon acts as both a wave and a particle. If you set up an experiment to detect its wave properties, you won't see its particle properties; if you set a detector to look for particle properties ahead of the wave detector, then you will only see particle properties. If you have two entangled photons and you detect one as a particle, the other should exhibit particle properties as well.

The U of W experiment will use that to show information going back in time by setting up a detector that will show photon A as a particle or a wave. Photon B, meanwhile, will be taking a leisurely trip through a couple of 10 km spools of fiber-optic cable to another detector. That second detector can be manipulated in some manner to detect it as either a particle or a wave. In Mr. Cramer's theory, photon B has to send the information about its pending state back in time 50 microseconds to photon A so A knows what property to exhibit at its detector.

Well, maybe. All we really know is that measurement of A will disrupt it in a manner that will be duplicated in B at the instant of measurement. However, measurement of B will also disrupt in a way that will be duplicated in A. But, since we've disrupted A already, we really can't tell anything about what B's measurement means without examining A again. In other words, the measurements are independent events. Just because you try to make B behave like a wave and A happened to look like a wave doesn't mean that the B measurement was transmitted back.

To put it another way, I don't think this is going to work.

It doesn't really matter, because the late Dr. Isaac Asimov introduced the world to Thiotimoline, a chemical that dissolves 1.12 seconds BEFORE water is added to it, in 1947.

By the time Asimov was working on his doctorate in Chemistry, he was already being published in “Astounding” magazine (later known as “Analog”). He wrote three stories about the chemical, the first of which was a scholarly-looking document with the ponderous title, “The Endochronic Properties of Resublimated Thiotimoline.” The third of the stories was a “speech” given before the “American Chronochemical Society” explaining the dangers the chemical posed to the Free World if it was in the hands of the Soviet Union.

Because Thiotimoline dissolves before water is added, you could use it to predict events. You begin with the “endochronometer”, a device which automatically delivers the water to the Thiotimoline, which dissolves 1.12 seconds before the water hits it. You could hook a second endochronometer to the first which, when the chemical in it dissolved, triggered the first to release its water. You could create a battery of these devices to extend the time from the triggering of the first endochronometer to the dissolving of the Thiotimoline in the last. In fact, about 77,000 of them would result in a process taking about 24 hours.

The practical upshot of this is that you could forecast the result of an event by deciding that, upon one outcome you would trigger the battery while on another you would not. Then, if you checked the last endochronometer 24 hours before the event, you would know the outcome based on whether the Thiotimoline had dissolved or not.

Suppose you wish to bet on a football game. If team A wins, you will trigger the endochronometer batter at 7 PM the day of the game. If they lose, you will do nothing. You check the last endochronometer at 7 PM the day before the game; if it has dissolved, bet the farm on team A. Otherwise, put your 401k on team B.

Of course, Thiotimoline is a fiction, but in one of Asimov's stories on the subject, he builds a wondrous sequence of events to demonstrate its potential for international catastrophe.

At the time he wrote the first story, which had the look and feel of a scholarly piece, Asimov's doctoral review was coming up, and he was naturally concerned that some of the thesis examiners would not be amused by a doctoral student taking time from his work to write a lampoon thesis, so he asked John Campbell, editor-publisher of “Astounding”, to publish the story under a pseudonym. Campbell, who enjoyed the story enormously, agreed then promptly forgot, so the story was published under Asimov's name.

The story was an immense success, and, according to Asimov, the New York Public Library was pestered immediately by students wanting to check the (fake) references from the “article” so they could learn more about the subject. While he should have been pleased, Asimov was devastated. He figured that the academicians at Columbia, where he was taking his doctorate, would not be amused at his lampoon of scholarly writing.

He was, therefore, relieved as he went through his orals that the professors treated him well and made no reference to his story. As he reached the end of the exhausting process, one of the professors intoned solemnly, “Asimov, can you tell us something about the endochronic properties of resublimated thiotimoline?” Asimov, seldom a man at a loss for words, was unable to answer because he was laughing so hard.

He got his PhD, demonstrating that, at Columbia at least, even stuffy professors have a sense of humor.

Tuesday, November 28, 2006

More Pontiff-ications

There are some people that if they don't know, you can't tell 'em. ~ Louis Armstrong

Is anyone else tired of Pope Benedict XVI yet?

I suppose I should appreciate such a gold mine of ideas for posts, but frankly he's getting to be a bore. To wit:
  • Benedict announces a “seminar” to be held to review the Church's position on Darwinian evolution, which prompted me to review the Galileo Caper.

  • He announced a desire to return to the Latin Mass, not necessarily a bad thing in itself, but, in his case, it's an alarm klaxon shrieking about a Pope wanting to return to the past.

  • Back in the science venue, he warned scientists, essentially, that there were things that man was not meant to know, using his Icarus metaphor. Those last two items resulted in Benedict Rides Again.

Now he is warning scientists not to go around making alarmist predictions unless they are absolutely, positively certain that the prediction is accurate, prompting this outburst on my part.

Scientists, the pope says, should know their limits. I wish Benedict knew his.

His latest mouthful is believed to be in response to an assessment that says oceanic fish stocks will be flat gone by 2050. It is quite true that we can't know something like this for sure, but given that we have brought numerous species to extinction or very near to it, the possibility is quite real.

Interestingly, I haven't seen a single word from Benedict about the alarmist press reports that claim terrorists are cranking out sarin in their kitchens from castor beans, some idiot can make “dirty” bombs from the radioactive material in smoke detectors, and someone can mix up a liquid bomb in an airplane toilet using household products that is powerful enough to blow the plane up. A brief reading of the Dick Destiny blog will show you that grinding castor beans does not produce usable sarin, you'd need 10 million smoke detectors to gather enough material to make a dirty bomb (sort of like trying to make an atom bomb by scraping the radium off glow-in-the dark wrist watches), and the liquid bomb requires setting up a titration lab experiment for about three hours in the airplane john.

This and other similar pseudo-science (which is almost a compliment when talking about mainstream media news science reporting) doesn't seem to bother the pope. But, issue a warning based on real data that could have serious ramifications for the world's population is “alarmist.”

This is clearly a pope who would have declared the Copernican system to be a heresy because it upset the Aristotelean framework supported by the Church. He probably would have had Galileo burned at the stake, rather than sentenced to house arrest. In fact, he never would have allowed publication of the “Dialogue on the Two Chief World Systems.” He would have proscribed belief in quantum mechanics (he may yet) because it destroys the concept of pre-destination. And evolution would have been right out (and it may yet be).

I'd suggest that Benedict stick to religion for his pronouncements, but given that he's already managed to tick off the Islamic world, we'd be better off if he would simply shut up.

So what does it matter if the pope shoots his mouth off? He's still essentially a religious figure, and religion and science have managed to get along for some centuries now, haven't they? Yes, they have, to a point. But, let's not forget that school systems have been pressured in the U.S. to teach Creationism as a “scientific” alternative to Evolution; some have been faced with campaigns to stop teaching Evolution altogether. While the pope's statements apply primarily to Catholics, fundamentalist Christians would jump on his pronouncements if they supported their blinkered view of the universe.

Benedict is that most dangerous of individuals, an ignorant man in a position of power. Thus far, he hasn't invoked papal infallibility; that would require issuing a papal bull expressing these opinions. But, unless there is someone around him with a modicum of sense, that can't be far off. And, it's unlikely that Benedict surrounds himself with any independent thinkers.

There has been a small but vocal group of atheist thinkers, led by Richard Dawkins, a noted author of books on genetics and evolution, calling for the abolition of religion. I feel that such an attitude is extreme and destructive, but the more Benedict talks, the more I understand why Dawkins and his supporters feel the way that they do, although I don't agree with their draconian approach. Science thrives on open discourse and free communication; religion has always engendered the opposite attitude, restricting free thought, often severely punishing those who would express contrarian views. Benedict would better serve his congregation by keeping his mouth shut and working to ease conflict in the world rather than foment more of it.

Someone needs to explain to the pope that this is 2006, not 1506.

Saturday, November 25, 2006

To Infinity and Beyond!

Hot damn! We is down among 'em! -- Eugene Cernan, Apollo 10

You will be hard pressed to find Gene Cernan's quote on any NASA site. The only way I was able to verify my memory of this moment was by going to Google, where I found a post I made several years on a newsgroup asking if the quote was accurate. Apollo 10, in case you've forgotten (and you probably have) was the mission that tested the LEM, releasing it from the command module and letting swoop down to within 15 Km of the Moon's surface. It was that moment that prompted Cernan's slightly profane outburst.

Of course, NASA didn't approve of one of their boys acting like a human being. But, Cernan was forgiven and even became the last man to set foot on the Moon.

It just goes to show that the spirit of adventure that was the Apollo program seems to have disappeared.

We desperately need to get a sense of adventure again. The Space Ship One pilots had some of that, but they spoiled it by crying after just about every mission. But, given the lack of testing and the last minute changes that were being made just before takeoff, I guess I'd cry for joy about getting back in one piece, too.

But space flight today is so scripted. There are the endless press conferences with shuttle crews, all saying just the right things, thanking everyone until they're blue in the face. The Chinese taikonauts must have taken a set of dialog cards with them. I know things suffer in translation, but the quotes from these men were nothing more than propaganda. They surpassed even the Soviet cosmonauts in praising the nation, the workers, and, of course, the government.

There used to be a more excited approach to space flight. Perhaps it was a little "cowboy", but it was very human. Alan Sheppard, having sat on the launch pad for next to forever, had to take a whiz in his suit. He later exhorted Mission Control to “fix your little problems and light this candle.” John Glenn, so exuberant he forgot he was supposed to be doing a scientific mission, kept being amazed by the view. Joking and chatter was common, because this was the unknown, and people tend to make jokes to avoid thinking about how scared they might be.

On Apollo 8, Frank Borman read from Genesis as they slingshotted around the Moon. NASA wasn't expecting this. But, this mission was changed at the last minute from an earth-orbital test to the lunar fly-around in an attempt to one-up the Russions. With so much uncertainty about whether they were going to succeed, astronauts giving a nod to the Almighty seemed like a very good idea.

It's not much like that anymore, but maybe it's because of the missions. When you're shuttling supplies to a space station and bring back the trash, it must be a little hard to get cocky. The shuttle doesn't go anywhere. The Mercury and Gemini missions just went up and down, too, but they were preparing the way for the big trips. We don't have any big trips, now, except for the ones run by our robots (who are doing a heck of a job on Mars and around Saturn). Oh sure, there's talk about Mars, but with no funding, no one is going anywhere soon. We need a mission, a real long range goal, to capture the old spirit.

Gene Cernan has another quote, of more recent vintage. As the years since his last trip to the Moon passed with no new endeavors for manned space exploration, he said, “Yes, I am the last man to have walked on the moon, and that's a very dubious and disappointing honor. It's been far too long.”

That's the kind of attitude that will get us to Mars.

Thursday, November 23, 2006

Giving Thanks for MGS

Not fare well,
But fare forward, voyagers.
~ T. S. Eliot

As duly noted in Gog's Blog, I have entered into a period of intense goofing off (which has involved doing a bunch of stuff instead of properly lying around watching football), so I intended to just wish the occasionally readers who pass through this spot a Happy Thanksgiving and leave it at that.

But, I can't let the day pass without a kind word for the
Mars Global Surveyor (MGS) which may have sent its last picture post card to Earth (as I recently noted). NASA is about ready to concede that MGS may no longer be reachable. MRO's younger but more powerful sibling, Mars Reconnaissance Orbiter (MRO) has looked and looked but has been unable to locate the silent satellite. Without knowing where MGS is and what its condition is, controllers have very slim chances of ever regaining contact.

Well, it's not like MGS has been goofing off. It's sent around 240,000 photographs back that will keep planetary scientists busy for years to come. Only the rovers Opportunity and Spirit approach it for success in exploring Mars.

MGS will hang around in orbit for some years to come before atmospheric drag causes it to drop toward the Red Planet. Given how thin the Martian atmosphere is, it may well reach the surface, creating a small crater. If it does, maybe someday Martian explorers will locate it and say a few words over this device that paved the way for them.

Thanks for a job well done, builders and operators of MGS.

Tuesday, November 21, 2006

Our Neanderthal Ancestors?

I use the term Struggle for Existence in a large and metaphorical sense, including dependence of one being on another, and including (which is more important) not only the life of the individual, but success in leaving progeny. ~ Charles Darwin

The fascination with Neanderthal just goes on and on.

Given what a lousy rap he had for years, I suppose it's appropriate that we now pay some attention to getting the picture right. We've now definitely established that Neanderthals walked as upright as you and I, were a successful species for hundreds of thousands of years, and probably had brains that made them potentially as smart as we think we are. We don't know, though, why they changed so little in that long period of existence, to the point that they used similar tools from beginning to end, never created cave drawings or other art, and may not have spoken a formal language.

We now know that Neanderthal and our immediate ancestors (anthropologically speaking) Cro-Magnon co-existed in several places quite possibly for 10,000-40,000 years. We have absolutely no idea how the two species got along, whether we lived and let live or massacred them at every opportunity. And, of course, did the two species interbreed?

That last has nothing to do with prurient interests. If there was interbreeding, then the Neanderthals might not have been wiped out by Cro-Magnon or simply died out on their own. The two species might have merged, at least to some extent.

So far, DNA analysis has not revealed any traces of Neanderthal genetic inheritance in modern humans. That isn't a definitive “no” to the interbreeding question because there's a lot more DNA to investigate, but so far it doesn't look good. In fact, scientists might have thrown in the towel on the subject by now were it not for some very suggestive discoveries. (No, I'm not going to make any cheap jokes about football defensive lineman, tempting as that may be.)

The most recent data comes from an analysis of bones discovered in 1952 which appears to clearly show a mix of modern human and Neanderthal characteristics. It's not the only such skeleton, and it falls into that tantalizing overlap era by being 28,000 years old. To date, though, no one has been able to successfully extract DNA from such a skeleton, which could potentially put the issue to rest once and for all.

The possibility of interbreeding is certainly imaginable, but the question is whether such a mating could produce any offspring. If it could, would the offspring be sterile, like so many hybrid species are? We have hints, but nothing definitive.

In general, I think a lot of people, including scientists, would like to think that there was successful interbreeding between the species. It would be nicer to think that the older species merged into ours rather than being killed off or wandering off into the Stone Age sunset to die in some lonely place. In fact, it's interesting that scientific attitudes have changed to some extent regarding whether modern humans were running woolly mammoths, saber-toothed cats, and woolly rhinos into extinction.

Up to a few years ago, it seemed like every time an animal species and humans existed at the same time and place, it was assumed that the brainy hunters must have wiped out any species that no longer existed. The biggest problem with this idea is that it ignored the biggest extinction factor, climate. It also ignored that fact that, world-wide, the human population was a few million. There were almost certainly a lot more woolly mammoths on the planet than there were humans, and humans had other things to hunt for as well, including things that weren't as likely to fatally step on them. This is not to say that humans didn't hunt mammoths; they almost certainly did. But they also probably scavenged dead ones.

It's quite possible that humans killed the last mammoth, but the mammoths were on the way out due to major changes in the ecosystem that had nothing to do with human activities.

Having freed ourselves of killing of the mammoths, it appears that we'd like to be declared “not guilty” in the matter of Neanderthal's passing. Much as I hate to disappoint everyone, but evidence of interbreeding won't prove anything. The history of human warfare is filled with tribes and civilizations being destroyed with survivors being taken as captives, generally to be made into slaves. The slaves interbred with other slaves and with the conquerors. That is not a peacefully “merging” of two groups.

I don't think we'll ever conclusively know the answer to this one, but my money is on a declining Neanderthal population that was wiped out by a growing Cro-Magnon people. I am certainly willing to maintain an open mind on the subject, but it's difficult to imagine that a behavior pattern that's manifested itself throughout the historical period and shows itself even in the prehistoric evidence, where sites have been found showing signs of conflict with bodies having spear and/or arrow points embedded in them.

I guess one might be able to argue for coexistence if one could find a site that clearly showed simultaneous habitation by Neanderthals and modern humans. There have been sites located that were inhabited by both species, but one could have followed the other (or killed off the other and moved in). The problem is that both groups were not yet producing the kinds of artifacts (like pottery) that could help pin down whether they were trading and getting along with each other.

Someday a site may turn up that will clear us of the onus of having started our career by killing off the competition.

Thursday, November 16, 2006

Retirement Planning for Real?

There is just one thing I can promise you about the outer space program: Your tax dollars will go farther. ~ Werner Von Braun

I want to be very clear on this: I had nothing to do with it. I knew nothing in advance, I've got no friends on Mars (well, except for my able assistant), and I had no communications with the satellite before it went bonkers.

Of course, I'm talking about Mars Global Surveyor, which has gone incommunicado for the last couple of weeks. After writing about satellite retirements, though, I feel like I put a general hex out into space, looking for a victim. To bring you up to date, MGS, which has been returning high-quality pictures from Mars for nearly 10 years. MGS was to spend a Martian year photographing the planet as it went through seasonal changes, but, like the rovers, it was working so well that its mission was extended a couple of times.

In fact, MGS has been up there so long, it's become part of a crowd, what with Odyssey and the Mars Reconnaissance Orbiter (MRO) having arrived to look for water. Good a job as MGS has done, MRO takes things to a new level, taking pictures with such a high resolution, they can clearly show the rover Opportunity and its shadow). MRO has a new assignment right now, though: Find MGS and take its picture.

Back on November 5, MGS phoned home to say that it was having a problem with one of its two solar panels. Since the panels provide all the power for the satellite (there's no RTG), the loss of 50% of its power-generating ability was potentially serious. Soon after sending the message, MGS went silent, except for a brief transmission that seemed to indicate that it had gone into safe mode.

“Safe mode” is a condition used by satellite computers when something has gone seriously wrong. Basically, a condition has occurred which the device can't deal with, so it essentially “reboots” and sends an identification signal to let Earth know where it is. Then it waits for instructions. Unfortunately, since no one has heard from MGS, we can't say for sure where it is. If one of the panels has gone bad, it's possible that the satellite turned its remaining operational panel into a position to maximize the power generation. Unfortunately, this could result in the probe's antenna pointing in the wrong direction to communicate with ground controllers.

Ideally, once it's batteries were charged, the satellite would occasionally turn toward Earth and operate off battery long enough to communicate. But, it doesn't seem to be doing that. So, the MGS team has asked the MRO folks to try to find and photograph MGS. Assuming MRO can find MGS, given MRO's resolution capabilities, it's just possible the team might see enough detail to be able to formulate a plan to recover the Surveyor.

Even the rovers might get into the act. There is a possibility that Opportunity and/or Spirit could pick up a beacon signal from the ailing spacecraft. If they can, then the team might be able to get a fix on its position. It's a long shot, but no one is ready to give up.
The biggest problem is that time is running out. If enough power isn't being generated, MGS might not be able to communicate anymore.

Wayne Sidney, the MRO Flight Engineering Team Lead, is quoted in the Space.com article, pointing out that, even if MGS can't be recovered, it's been a game trooper that has been operational from Mars longer than any other satellite or lander. In other words, even if MGS has gone to the old satellite's home, no one can complain about its performance. Like the rovers, the Voyagers, Galileo, and the Pioneers, it has worked longer and better than anyone hoped. As I've said before, when we get it right, we really get it right.

He also mentioned that November 7 would have been the tenth anniversary of MGS in space. By coincidence, that was the very day that MRO fired up its main science equipment. “It really seems like there's fate involved in all this,” said Mr. Sidney. “MGS knew it was time to retire.”

I swear it wasn't my doing.

Tuesday, November 14, 2006

Spooky Entanglement

We become what we behold. We shape our tools, and then our tools shape us. ~ Marshall McLuhan

When people think of science fiction, there come to their mind almost automatically certain devices: Faster-than-light spaceships; sentient robots; and everyone's favorite, teleportation. The Star Trek transporter often figured heavily in plots and is probably the one thing from Trek shows (after Spock's ears) that comes to the average person's mind. If you asked those same people which of the inventions I mentioned above is least likely to see the light of day, I think most would say, “Teleportation, of course.” And, they'd be wrong because, while no one has beamed people up to the ISS yet, scientists have been teleporting quantum particles since 1997.

I can give only you a very vague idea of how this works because, quite frankly, it's complicated and downright spooky. In fact, it involves something Einstein once called “spooky action at a distance.” I'm going to try to summarize Brian Greene's excellent discussion of teleportation from The Fabric of the Cosmos, but if you find it hard to follow, don't blame Dr. Greene. The whole subject is typical of any quantum mechanical discussion; that is, it sounds like swamp gas to anyone who hasn't done the math and the experiments. But, like most things that rely on quantum theory, somehow it works.

Teleportation relies on something called “quantum entanglement.” Two particles, say a couple of photons, can become couple such that anything that happens to one of them is reflected in the other, even if they are separated by vast distances. How such coupled particles come about is beyond the scope of this blog (actually this whole discussion is beyond the scope of this blog's author, but I'm giving it the old college try), but suffice it to say that the effect works.

Therefore, I could have a photon in my lab in Alabama while my able assistant has its coupled partner on Mars (how he got to Mars, we'll leave to your imagination). If I perform a measurement on the photon in my lab, thanks to the vagaries of the Uncertainty Principle, I will alter some characteristics of my photon. Those alterations will immediately show up on the photon in Ohio. I don't mean the alterations will show up 18 minutes later by traveling at the speed of light; I mean they will occur at the same instant in both locations. That is Einstein's “spooky action at a distance.”

Before you go buying stock in AT&T Hypertelecommunications Inc., Dr. Greene says there's a fly in the ointment. The entanglement can only be determined by comparing the results of my measurements with data on the Mars base. To send that information, I have to call Mars by conventional means so my able assistant can compare them. In other words, the instantaneously transmitted spooky action is “coded”, and the only way to decode the result is the get my data.

So, we're not going to communicate faster than light, according to Dr. Greene, but entanglement can be used to teleport particles at the speed of communications, which means, in our example, getting to Mars in 18 minutes (plus the time to receive and assess all the data, as we'll see). So, how does teleportation work?

To begin with, you've got to keep in mind that, in quantum mechanics, one particle of a given type is identical to any other particle of the same type. All electrons, for instance, are created equal, as are all protons, quarks, leptons, muons, and so on. So, armed with that intelligence, let's teleport a photon.

To do so, we'll need three photons: Photon A, the one we want to teleport to Mars; photon B, sitting in my lab next to A; and photon C, located on Mars which happens to be entangled with B. Now, I could measure a property of A, but all that would do is alter some characteristic of that photon. I can, however, measure a joint property of A and B, such as whether the direction of their spins is the same or different. I don't measure what the actual spin direction is, just whether or not they're the same.

So, now I know how A's spin is related to B's, which means I also know how A's spin is related to B's entangled Martian buddy, C. Now it gets complicated (as if it wasn't already). I send my data to Mars, where my able assistant can take that data and manipulate C. Before we go further, keep in mind that my act of measuring the relationship between A and B has, by quantum theory, disrupted A and, more importantly, B. C, then is also disrupted in exactly the same manner as B. Still with me?

Here's the magic. My able assistant utilizes my data and the observed disruption of C to put C into the quantum state A was in before I made my measurement! In other words, in my lab, photon A is no longer in the state that it was in when I wanted to teleport it, but C on Mars is. Therefore, photon C is now photon A. Or, to put it another way, A has been teleported to Mars.

Now, this sounds like a nice academic exercise, but it's not. You can argue that all I've done is change properties at my lab and at the Mars lab. But let's take it another step. Suppose we teleport YOU to Mars (you don't think I'm crazy enough to experiment on myself, do you?). Here's what we need to do.

In my lab and on Mars, we have chambers filled with enough electrons, protons, neutrons, and so on to construct whatever object we wish to teleport (in this case, you). All of the particles in my chamber are entangled with those in the chamber on Mars. I also have a device capable of taking measurements of the joint properties of all the particles in you with the particles in my chamber. In the process, I'm going to have to alter all the particles in your body, which could involve disassembling your constituent atoms (you see why I wanted someone else to test this). After taking those measurements, I send the results to Mars, where my able assistant uses the data to set the quantum states of all those particles back to what they were before I took my measurements, and voila! There you are, standing on Mars.

This does raise an interesting metaphysical question, namely, is the you on Mars the same being that used to be on Earth? According to Dr. Greene, since at the quantum level all particles are equal, and we have replicated the states of all those particles to be the same as they were here in Alabama, at the quantum level you are the same. If you're the same at that level, you're the same at the macro level. But we're a long way from having to deal with this issue since this is all horrifically complicated and well beyond our current capabilities. Just trying to take the trillions of measurements (not to mention disassembling your body into atoms) is a staggering concept, as is the idea of setting up two chambers containing millions upon millions of entangled particles.

But, unlike faster-than-light-drives, at least quantum teleportation is a fact, and it has ramifications for the future of computing. Quantum computing, which puts forth promise of incredibly fast and powerful computers, has a potential problem . Data is stored in quantum bits or qubits which, to be useful, have to be transported from the material in which they are held to other computers. A good way to do this is by sending the state information from one particle to another particle using a using a third particle. In other words, you have to use quantum teleportation to transport the state in one computer to another. The initial experiments, described above, used identical types of particles. Now, a team at USC has managed to use a photon to transport the state of one cesium atom to another, taking a major step forward in both quantum computing and teleportation.

Scotty may not be beaming us up any time soon, but computers may be beaming our data from one place to another in our lifetimes.

Reference:
The Fabric of the Cosmos, Brian Greene, Alfred Knopf, 2004

Thursday, November 09, 2006

Retirement Planning

Live every day as if it were your last and then some day you'll be right. ~H.H. "Breaker" Morant

Space.com has an interesting article on the ultimate fate of Cassini, the thusfar hugely successful probe circling Saturn and peeking through the clouds of Titan. The article brings up something we don't often think about: Sooner or later, our wonderful satellites that circle various planets and meander through the Solar System, these magnificent machines, wear out.

We're not talking about the ones that bought the farm due to human error or aliens shooting them down (those pesky Martians) but ones that complete their missions and just run down. Many that orbit the Earth just sink lower and lower until the atmospheric drag becomes too great, at which point they “nose in”, ending as flaming streaks in the sky. Occasionally, though, very large things come down, like Skylab and Mir, which require a more controlled approach. The usual intent is to drop them in the Pacific Ocean because, well, it's big and hard to miss.

Of course, Australians might point out that every time something large is brought down, pieces of it end up scattered across the Outback, but what's a few dead kangaroos amongst friends.

Some satellites were intended to come to a violent end. The Ranger series was designed to look for potential lunar landing sites. I vividly remember the pictures coming back as they descending rapidly to the Moon's surface before cratering. We had never seen the ground of a non-terrestrial place with such detail before. Even though the picture quality would be considered miserable today, it was great science then.

The Surveyors follow the Rangers, testing out landing methods that would ultimately be used by the LEMs. The Surveyors actually touched down softly on the Moon, where they sit to this day. The Apollo 12 mission, I think it was, landed near one and brought back a chunk from the satellite. This is the famous bit of jetsam that, when returned to Earth, was found to have bacteria on it that could be resuscitated, giving us the realization that microbes could conceivably hitch a ride inside a meteor and arrive on Earth.

Other probes were like that annoying little rabbit; they just keep going and going and going. Two of the Pioneer probes that sent back grainy pictures of Jupiter are chugging along at the edges of the Solar System. One of them was still transmitting weakly up to a couple of years ago. But the long distance record for both distance traveled and furtherest area code calling in belongs to Voyager 1 and 2. These puppies passed the Pioneers long ago, thanks to the gravity boosts received from the gas giants and are either headed for, are passing through, or are nearing the heliopause, depending on whose interpretation of data you believe. Thanks to their radioisotope thermoelectric generators (RTGs), they still have a trickle of power to run instruments and transmit back to Captain Kirk's ancestors.

Deep Impact, which shot a probe into a comet, is still chugging around the inner Solar System, fully functional and waiting for someone to come up with something for it to do. Ditto Deep Space One, which is putting along with its ion engine, patiently hoping for an assignment (I think there was a plan for a cometary flyby, but it's been a long time since I've heard anything about).

Occasionally, we've deliberately brought at least part of a satellite back. Stardust successfully landed in the desert, bearing interplanetary dust and comet grains. Genesis, as we painfully recall, had a little miscue in its circuitry that caused it – how shall I put it – to come a' tumblin' down and smack into the desert floor. There is an ongoing effort to recover the samples solar particles it gathered, but while the Genesis team is still assembling broken pieces, the Stardust team has so much data, they're letting the general public look for potentially interesting impacts in the aerogel.

Then there's NEAR, a mission to take an up-close-and-personal look at asteroid Eros. Seems the team had a dirty little secret they had kept since the outset of the mission. After accomplishing the mission goals, they took a device with no landing gear that was never designed to touch down anywhere and gently deposited it on the surface of the asteroid, a magnificent achievement.

Galileo, a warrior of a satellite, met a fitting end. On a mission to Jupiter, it had a malfunctioning high gain antenna that forced engineers to develop new data compression schemes. Then, despite going through intense radiation around the largest planet, it's mission was extended twice, and it sent back amazing images and data, kept on a tape drive that should have been fried several times over. It was the little-satellite-that-could.

It got to go out like a star, directed to dive into Jupiter's clouds, where it would burn up, becoming more atoms in the dense Jovian atmosphere. Galileo went out like a trooper, sending data to the last.

There are thoughts about doing the same for Cassini when it gets old in the tooth come 2012 or thereabouts. The trouble is that Saturn is surrounded by those beautiful rings, and any attempt to send Cassini into Saturn's clouds would have it passing through a dense portion of those rings. Once it started getting bounced around by the chunks of rock and ice in the rings, it's anyone's guess where it would end up. I'd have to believe, though. that more than a few scientists would like to take a shot at this option because so much could be learned about the makeup of Saturn's trademark rings.

Another possibility is to crash land on one of Saturn's moons. But, the RTGs would still be functioning and generating heat (there's almost zero risk they would burst open and contaminate the surface), and the heat could melt the surface ice, possibly doing localized harm to any potential ecosystem. Now, a functioning ecosystem on, say, Enceladus may seem like a long shot, but one of the overriding concerns of space exploration has been to not louse up anyplace we visit. Yes, we've been litterbugs on Mars and the Moon, but maybe we'll get to those places and clean up one day. Every attempt has been made, though, not to introduce anything that would alter even the immediate environment of probes to these planets.

The most likely possibility is to simply leave Saturn altogether. Cassini could be sent toward interstellar space, following the Voyagers and Pioneers; depending on the state of its much more advanced instrumentation, it could send back some interesting data. Alternatively, it could be sent inward, maybe to follow Galileo into the Jovian mists, or, with a gravity assist from Jupiter, it could head inward and possibly crash on Mercury or into the Sun.

Personally, I'd like to see it sent outward. It's just barely possible Cassini could send back data on Kuiper Belt objects and someday investigate the heliopause. Galileo, if I may be allowed a little more anthropomorphism, got to have its warrior's funeral, a blaze of glory no doubt. Cassini stands to still have some functionality, being more of a veteran explorer looking for one more mountain to climb or river to cross.

It's a big universe. Having one more human mission heading out into it seems like a fine idea.

Tuesday, November 07, 2006

Spreading the News

Whenever science makes a discovery, the devil grabs it while the angels are debating the best way to use it. ~Alan Valentine

So, the other day I was discussing how the Viking landers may have found life on Mars after all. When I think about finding life on other planets, I think in terms of how exciting it would be. Apparently, there are other people who are concerned about the concept. In fact, not too long ago, an article appeared that held that a policy was needed by NASA to provide guidance on how best to inform the ignorant masses that life had been discovered on another world. The centerpiece of the article is the brouhaha that surrounded our old friend, ALH84001.

When scientists announced that they thought they had found signs of microbial presence in the Martian meteorite, they were all over the news. As I discussed in my earlier article, there came to be considerable debate about what they found, and ultimately, it was held to be inorganic. Yet, when additional claims for that meteorite showing signs of bacterial activity and, even more recently, similar tracks were found in another Martian meteorite, the media at large ignored it.

The biggest difference is that NASA made a big deal the first time, with a press conference (which was hastily moved up due to a leak) and lots of hoopla. The more recent findings have simply been released by the researchers, with no press briefing, no media glare, just a paper to a scientific audience.

Of course, none of the evidence, including the new view of the Viking data, is definitive. All of it is open to other interpretations. What we need is to bring back some chunks of Mars that haven't been baked coming through the atmosphere and examine them in a proper lab. There was such a mission on the books, but, thanks to NASA's shuffling of money to the shuttle (and to the commercial rocket kiddies), it's been shelved.

Should there be a change of heart (and head) in Washington, the mission could be back. Should life be discovered beyond a shadow of a doubt, NASA has concerns about disseminating that information. On one level, premature release of findings could prove embarrassing should it turn out, for example, that results were skewed by terrestrial contamination. On another level, there seems to be a fear of panic in the streets.

Perhaps there's some cause for their caution. Given the state of reportage today, the first thing out of the media's collective mouth would be “PLAGUE!” or something similar. Reporters would be quoting from “The Andromeda Strain” and the end of H.G. Wells “War of the Worlds”, to show how when a life form meets bacteria from another world, the bacteria win.

By the way, has it ever bothered anyone else that Wells' Martians died from Earth's bacteria but no hunans were felled by the Martians' bacteria?

Considering that Martian meteorites have been falling to Earth for countless millennia and that we've found that bacteria can survive extreme conditions like those in space, we should have all turned green and died by now. Proper precautions should be taken, most certainly, but it should be as much to protect any possible Martian life as much as to avoid plague and catastrophe.

Of course, the possibility exists that, somewhere out there, there are life forms considerably beyond the bacteria stage. According to a recent article, we should be careful about trying to contact them. Apparently, some folks feel that, in projects like SETI, we might be inviting the Vogon Constructor Fleet to show up and build a hyperspace bypass.

I suppose that's natural given our own human history. We haven't done all that well when discovering new civilizations. It seems like, after an all too brief honeymoon period, one side decides that the other has to conform to its idea of civilization. This usually ends up with one or both of them severely dead.

I've written about the odds (here and here) of actually contacting other civilizations, the upshot of which was that it's a long shot. Even if we do manage to receive a signal from way out there, as things stand now, the conversations will be extremely slow. Personally, I'm not worried that Ming the Merciless is going to be showing up any day soon.

UFO fans, it goes without saying, would argue that aliens have been showing up for years, but I'm trying to stick to reality here.

I can't help having the nagging feeling that what worries people is not that the Galactic Empire is going to show up with a fleet to enslave us. What they're worried about is humanity losing its exalted position at the center of the universe. Every religion makes humans the central creation of God (or the gods, depending on your persuasion); finding out that there are sentient beings on a rock circling 51 Peg or wherever is going to seriously rock some people's psyches.

It's hard to imagine how the general populace will react. In some theories, people will be panicked or distressed; in others, people, realizing we are just one aggregation of beings among many others. Perhaps, they would work to find ways to go meet those beings.

I really don't know how the majority of people will react. I do know that working out some convoluted means of distributing the news will only sow confusion and possible distress. Just tell us what you're finding, NASA and other searchers. Don't sugarcoat it, and don't overhype it. If you find bugs on Mars, show them to us. If ET calls, display the message.

Most of us are all grown up; we can handle it. The rest will just have to deal.