Saturday, December 31, 2011

10 Years After 2001 and Still no Space Odyssey


It was in 1951 that a writer by the name of Arthur C. Clarke published a short story called The Sentinel that postulated a future for the human race among the stars. In time, the short story would be expanded into the 1968 novel and film 2001: A Space Odyssey. Now, as 2011, 10 years past the title year of 2001, ends, so far, humans are still pretty much as grounded as they were the day The Sentinel was published 60 years ago.

So, where did we go wrong?

Answer: the political climate changed.
In 1961, president John F. Kennedy famously declared that America would land a man on the Moon and return him to Earth before the end of the decade. While that may have been just talk in another time, before or after, in the 1960s, it was serious business as the Cold War was on the verge of becoming a hot one. While coming about with neutral aims, rocketry quickly became a military science. By the 1950s and the advent of nuclear weapons, the capabilities of a given nation's rockets was a symbol of that country's power. The longer the rockets could fly, the greater the capability of delivering atomic death over vast distances. When the USSR launched Sputnik into orbit in 1957, it was obvious that Soviet rocketry was ahead of American capabilities. Theoretically, with rockets capable of launching payloads into orbit, the Soviets could rain death from the heavens of any city in the world. So, in order to keep the balance of power even, American scientists had to work fast to equal their Soviet rivals. And they did. By the time 2001 hit theaters, NASA was finalizing its plan to launch astronauts to the Moon. Think of it: in the span of just 7 years, humans went from an Earth-bound species to one poised on the pinnacle of traveling to another world.

So, in 1968, who would have expected the enthusiasm for space to dry up virtually overnight?
Placing oneself back in 1968, if we looked at how far we had come in just a decade (Earth-bound in 1957, getting ready to go to the Moon in 1968), how could one not expect that in, say, perhaps another decade, we could be going on missions to Jupiter, just like in the movie? In the late 60s, only infinity was the limit. Unfortunately, and ironically, by winning the space race in 1969, America killed the enthusiasm for space exploration.

With Apollo 11's touchdown in the Sea of Tranquility and return to Earth, President Kennedy's promise of landing a man on the Moon and return him safely home had been fulfilled, the Russians had been beaten, and the national pride that had so publicly been put on the line for all the world to see was intact. Following Apollo 11, many people simply could not name any good reason to go to the Moon at all. By the start of the 1970s, the Vietnam War was escalating and the booming economy of the 60s that fueled the space race was beginning to sputter. With the cost of everything on the rise and wages not rising accordingly, in the eyes of many, the drive to go to the Moon and beyond, the very idea that gripped Americans of all economic, racial, and ethnic classes of the 60s seemed a waste of money. For a a few years, NASA used scientific research as reason to go to the Moon but, come 1972, the powers that be had other ideas and it was announced that Apollo 17 would be the last trip to the Moon and that three future missions, Apollo 18, 19, and 20, would be scrapped and NASA would focus on undertakings that it deemed to be more friendly to the national treasury.

So, come 2011, we humans find ourselves, at least in terms of manned spaceflight, worse off than we were in 1968 as not only can't we go to the Moon, but we can't even launch ourselves into space without hitchhiking a multimillion dollar ride with, of all countries, Russia, the nation that we beat in the space race 4 decades ago. In reality, the self-sufficient space cities orbiting Earth, permanently-manned lunar bases, outposts on Mars, and star ships that would take us beyond our solar system and deep into the cosmic sea are still as much science fiction as they were 4 decades ago, a testament to the folly of turning away from technology.
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Tuesday, December 27, 2011

Examiner for weeks of 12/11, 12/18


A little belatedly, but here's a 2-week Examiner roundup.







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Sunday, December 25, 2011

The Planet of Bethlehem?

The Star of Bethlehem was probably a planet.

One of the greatest mysteries of the Bible and astronomy is the Star of Bethlehem, which guided the Magi on their journey to the baby Jesus. The description of the star in the Bible leaves a lot of questions, and just as many possible answers to its true identity.


One problem, by far the biggest, must be confronted right before we can even start to narrow down the possible identities of the star: no one knows exactly when Jesus was born. Our current calendar is based on the birth of Christ. Unfortunately, this is wrong. It is now thought that Christ was actually born in the span of 8 to 4 B.C. In the Bible, the Holy Family fled into Egypt to avoid the wrath of King Herod, who died in 4 B.C. Thus, that year is the last possible year in which Jesus could have been born.

Now that our time frame has been narrowed down, we can start looking to the sky. There are two schools of thought about the Star of Bethlehem: it was either astronomical or astrological.Astronomical possibilities include supernova, planets, comets, and conjunctions. In the year 7 B.C., there was a conjunction of Jupiter and Saturn. However, this is very unlikely as the planets were about a degree (little finger at arm's length) apart. Unless the Magi had very poor eyesight, there is no way that two planets this far apart could be mistaken for a single object. Comets have been suggested, especially since they were often described as “hanging” in the sky. This is exactly as the Star was described in the Bible. A last possible interpretation is a supernova. A bright object was seen for about 70 days in 5 B.C. By Chinese and Korean astronomers. This may just be it, but there's a problem: the star was described as moving, which leads into the other school of thought: astrology.

People at this time were almost universal believers in astrology. A notable exception here were the Jews, who were forbidden to practice astrology at numerous spots in the Old Testament. As far as everyone else was concerned, heavenly bodies had special meaning.

One thing we know was that the Magi came from the East. Considering the geographical location of Judea, “East” almost certainly meant Persia. In Persian language, the word “magi” referred to Zoroastrian priests, who practiced medicine and magic (“magic” comes from “magi”), which could also include astrology, at which the Persians were very sophisticated.

One particular passage in Matthew can greatly narrow down possible candidates for the true Star of Bethlehem. According to the Gospel, “the star which they had seen in the East went before them till it came and stood over where the young Child was.” If this is to be believed, the Star was a planet. Over the course of months, a star's position will change as it rises about four minutes earlier each night. Stars don't stand still, but planets do.

Observe a planet over the course of a year, noting where it is in the constellations. For most of the time, it moves forward. However, there are times where it stops, reverses course, stops again, then continues forward. This apparent change in direction called retrograde motion is an optical illusion caused by the Earth passing the slower planet as both orbit the Sun. A comparison can be made to passing cars on the highway. As you pass, the slower car seems to travel backwards. The same is true of planets.

Besides retrograde motion, there is more. Planets and constellations had different significances. Jupiter was widely considered to be associated with kingship. The constellation of Aires the ram was often associated with Israel/Judea. Putting this information together with the knowledge that the Star of Bethlehem was almost certainly a planet allows one to start putting the puzzle together.

In 6 B.C., an astronomical/astrological event that fits the bill very nicely occurred. In that year, the planet Jupiter (planet of kingship) moved into the constellation of Aires (the constellation for Israel/Judea). Thus, this could be interpreted as a sign that a new king of Israel was born. To add even more weight to the hypothesis, Jupiter first appeared as a morning object in the East. At this time, the Sun was also in Aires (Jupiter was rising just ahead of the Sun). In astrology, any constellation is at its most influential when the Sun is in it. Also, it was believed at the time that planets were at their most powerful as they emerged in the East after a period of invisibility in the Sun's glare.

As it would have taken the Magi months to reach Bethlehem from Persia, this also explains the motion of the Star. As time progressed, the Magi could have observed Jupiter slow down and stop before going into retrograde motion. The stoppage could have coincided with the arrival of the Magi in Bethlehem after stopping in Jerusalem and being told of the prophecy predicting the Messiah's birth there.


This is by no means more than a hypothesis. The Star of Bethlehem will probably never be conclusively explained. Either way, Merry Christmas!


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Wednesday, December 21, 2011

'Doomsday' is Only One Year Away: Science Takes on the Maya Calendar

The Caracol: ancient Maya observatory.

Do you realize what day it it? If you didn't, it's December 21, and according to some, we all have exactly 1 year to live as, come this date in 2012, the world will be destroyed by some as yet unknown worldwide cataclysm.

Ah, yes, the 2012 doomsday fears arise again, but are they founded in fact or fantasy?

Okay, before we start examining where the fear came from and whether we should even worry at all, let's run through the 2012 doomsday scenario first. On December 21, 2012, the Maya Long Count calendar runs out. Now, while no one has used the Classic Maya calendar in hundreds of years (the great Maya civilization in Southern Mexico/Central America collapsed around 1000 A.D.), some people read some ominous overtones into this whole idea of time just running out, which has lead some to believe that, since they were the only civilization with a calendar that ever ended at a fixed point in time, the Maya knew something that no one else did: the exact date the world would end.

Now, that's 2012 as told by the fear mongers, what about 2012 told by science and history?

Understanding the whole 2012 doomsday fear requires a mix of Maya history and religion, which will then come together quite elegantly in the end. First off, Maya religion was in itself quite a convoluted mix of mythology, the most important of which was the myth of the Hero Twins, as this story told of the triumph of life over death that just may be the basis for 2012.

The Maya, so far as we know, were the first people to possess rubber, which they used for, among other things, molding into giant balls (about 10-12 inches in diameter) that were used in a ceremonial ballgame that represented the triumph of life over death by recreating the myth of the Hero Twins. As for the story, it went as follows.

A Maya ritual ballcourt. Note how high the hoop is on the wall.

Way back when, perhaps at a time when the game was more about fun, a Maya king and his brother liked to play the ballgame, the object of which was to knock the ball through a hoop high on a wall without using one's hands or feet. Obviously, with the useful appendages out of play, the game could go on for days, with the first team to score winning. Unfortunately for the king and his brother, their ball court was just over an entrance to the underworld and the sound of the heavy ball bouncing all over the place started to irritate the Lords of Death, who also just happened to be ball players. Getting fed up, the Lords of Death invited the king and his brother to the underworld for a game. Accepting the challenge, the king and his brother entered the realm of the dead and squared off against, and lost to the Lords of Death. The king and his brother were then sacrificed. However, the story wasn't done: the king had twin sons of his own, who also liked to play the ballgame. In time, just like their father and uncle, the twins ball playing annoyed the Lords of Death, who then decided that they were going to try and go 2-0 against the humans. Long story short, the twins beat the Lords of Death, sacrificed them, and then resurrected their father and uncle as the Sun and Moon, respectively, thus, life triumphed over death.
A highly stylized representation of the Milky Way void as a monster swallowing the souls of the dead. A copy of the coffin lid for king Pacal the Great.

Onto the astronomy, the Maya were perhaps the greatest astronomers in history until the Renaissance, with achievements to their credit that still stun modern scientists. However, like the Greeks, the Maya were an interesting people in that they made the most accurate astronomical measurements of their day, yet still clung to mythologies characteristic of far more primitive peoples. For the Maya, one facet of this mythology was the idea that the Milky Way was the road to the underworld and a dark rift in the Milky Way itself right above the famous Teapot asterism was the actual gateway. Okay, fine, so what?


Back to the Hero Twins myth. Remember that the Twins resurrected their father and uncle a the Sun and Moon. In releasing their father (now the Sun) from the underworld, the twins were creating, according to the Maya, a “new Sun,” or cycle of life. Now, back to the ballgame. While no one knows the exact symbolism involved, there is agreement on the idea that the ball represented the Sun. So, if the ball represented the Sun and the players the Hero Twins and Lords of Death, it only makes sense that, by the winning team knocking the ball (Sun) through the hoop, they were thus representing the Hero Twins resurrection of their father as the Sun by shooting the Sun out of the underworld through the gateway, represented by the hoop on the wall. Now, back to astronomy. It just so happens that, due to precession of the equinoxes, the location of the Sun on any given day against the background sky changes over time. Now, perhaps one of the Maya's most remarkable astronomical achievements: on December 21, 2012, the Winter Solstice Sun will rise exactly in the center of the dark rift in the Milky Way, symbolically rising out of the underworld and representing a new cycle of creation, at least according to the Maya.

So, does this mean the world will end?

Ironically, for all the fear their calendar has created, according to the Maya, one cycle running out and another starting meant that the world could end, not that it would end. For a really interesting cosmology, one only has to look at the history of Maya timekeeping. The Maya (and other Mesoamericans before them) were interesting in that they believed that time was cyclical, not linear. So, being obsessed with cycles, it was only natural that that Mesoamericans started looking for them in nature. Being farmers, it was important for these early people to ascertain the length of the year to better ensure successful harvests. So, as every other primitive farming culture did, the Mesoamericans found the year to be about 365 days long. Now, for reasons unknown, the Mesoamericans used not one, but two calendars, the other being a 260 ritual one that was used for divination purposes. Now, here's the big unknown: which came first, the two calendars or the realization that they would line up exactly every 52 years? While the answer to that question will never be known (the Olmecs who developed it left no writing), the impact of the calendar would last for centuries, with the Maya taking it to new levels of sophistication.

As with some people today, the Mesoamericans found the notion of time running out to be a little unnerving. However, unlike today, this fear was held by the entire population. So, as the 52-year calendar round entered its final days, the priests would up the prayers and demand greater sacrifices in the hope that the gods would let the world continue to exist. Well, by looking at the fact that we're still here, those Maya priests must have been pretty good! Now, despite the fact that the end of the world had been successfully averted every time in the past, the thought of confronting doomsday every 52 years left the Maya rulers/priesthood (on whom the continued existence of the world hinged) uneasy. So, some unknown genius came up with a big idea: why not postpone the end of the world by finding a longer cycle of time so that we don't have to worry about it anymore? Well, the idea took off and, in time, the Long Count, which ran 5,125.25 years, was created.


The Maya were so obsessed with timekeeping that they even built calendars into their pyramids. This one has 91 steps on each side plus a temple on top (94 x 4 = 364 + 1 = 365).


By looking at the cycles contained within the Long Count, it quickly becomes apparent that the Maya had a true love of numbers and/or had too much free time on their hands. The breakdown of the units of time contained within the Long Count is a follows:

1 day = 1 K'in
20 days = 20 K'ins = 1 Winal
360 days = 18 Winals = 1 Tun
7200 days = 20 Tuns = 1 K'atun
144,000 days = 20 K'atun = 1 B'ak'tun
1,872,000 days = 13 B'ak'tuns = 1 Great Cycle (completion of Long Count)

Obviously, with the 5,125.25 year Long Count complete, the Maya must have felt more than secure in the knowledge that they would never have to worry about the world coming to an end in their lifetimes ever again, as if the gods somehow had to obey the will of man now that a longer time cycle had been created. Pretty funny, isn't it?

Okay, back to the present.

If you have made it this far, you (hopefully) have come to the logical conclusion that there was no way that the Maya could have predicted the end of the world as the Long Count is a human construction that has absolutely no basis in nature. Simply put, the Maya hated the prospect of having to worry about doomsday every 52 years, so they decided to create a longer cycle (the Long Count) so that they wouldn't have to worry about it anymore. So, come 2012 and the end of the Long Count, why worry? The world never ended at any of those 52 year calendar rounds, so why would it end now at the end of a Great Cycle? Answer: it won't, the Long Count means nothing and desperately needs to be confined to the realm of pseudoscience junk like astrology, tarot cards, and all other forms of divination, not a single one of which has stood up rigorous scientific scrutiny.


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Saturday, December 17, 2011

Canon 70-200 2.8L IS Mark I: Quick Review


Tech Specs
Focal Length: 70-200mm
Dimensions: 3.4 x7.8 in.
Weight: 3.2 lbs.
Maximum Aperture: f2.8
Minimum Aperture: f32
Diaphragm Blades: 8
Front Element: non-rotating, non-extending
Optical arrangement: 23 elements in 18 groups
Autofocus Mechanism: USM
Closest Focus: 4.3 feet
Maximum magnification: 1:6.3
Filter Size: 77mm


Disclaimer: I rented this lens a few awhile back and used it to shoot some high school sporting events. So, the vast majority of pictures made with this lens being of minors, I've decided not to include them for obvious reasons.
The test was also done on an APS-C format camera.



Background
The Canon 70-200 2.8L IS can trace its roots back to Canon's “Magic Drainpipe,” the 80-200 2.8L that was in the original generation of AF lenses. In 1995, Canon ceased production of the 80-200L and released a new 70-200L, which added a Ultrasonic motor and 10mm at the wide end. With its lightning-fast AF and low light capability, the new 70-200L became the workhorse lens for many an action shooter. In 2001, Canon took a good thing and made it better by adding image stabilization to the popular 70-200L, thus creating an even more well-rounded lens. Then 70-200L IS would remain in production until 2010 when Canon introduced a “II” version. Now, with the new lens on the market, the old one can be had for reduced prices, but is it any good?
Build Quality: 5/5
The Canon 70-200 2.8L IS exemplifies “L” build quality. To start with, the lens is all metal. Second, the lens is internal focusing and zooming, which means that it never changes length no matter what you do with it. On top it all off, the “IS” version, unlike the un-stabilized 70-200Ls, is weather resistant. To see this, just look for the rubber gasket at the mount that will prevent junk from entering your camera at the camera/mount connection, the weakest link in the weather-resistance chain. Moving onto the rings, both are rubberized and highly textured to provide ample grip. The outer focus ring doesn't spin during AF thanks to the USM focus mechanism. Speaking of the rings, they move as though they are floating on air and are a true pleasure to use.
Autofocus: 5/5
Being a Canon USM lens, focus on the 70-200 2.8L IS is fast, accurate, and silent. Also, being USM focus drive, you have the ability for full time manual override and a stationary focus ring during AF. In addition, Canon was nice enough to include a focus limiter switch that will prevent the lens from focusing at its closest possible distances in order to speed up the AF. In practice, unless you're torture testing the AF capability of the lens, such a switch is probably useless.
Optics: 4/5
Optically speaking, the Canon 70-200 2.8L IS is, while not bad, not exactly sharp wide open, either. Stop it down to f4 and it's razor sharp across the focal range. Heck, I'd give the edge on wide-open sharpness, at least on the wide end, to my ancient Tokina 80-200 f2.8, which was from back in the 80s! If sharpness is your prime concern, consider this a f4 lens, which pretty much negates the need for paying all that extra cash for less then ideal wide open performance, especially when considering the price class of this optic. Now for the good stuff. Distortion is nil, vignetting wide open (at least on APS-C) is minimal, and CA is very well controlled. By the way, the across the frame sharpness is very good with virtually no falloff in the corners.



Competition:
The short, fast telephoto zoom lens is a very crowded market segment for the simple reason that such lenses are so doggone useful that everyone wants a piece of the action. In camp Canon alone, there are 4 more 70-200Ls, a standard f2.8 and f4 and a stabilized, weather-sealed f2.8 Mark II and f4. The prices range from $650ish for the 70-200 f4L to over $2,300 for the 70-200 f2.8L IS II. In the middle of this price range, there are 70-200 f2.8 Sigma and Tamron alternatives, too. The non-stabilized Sigma is considered to be optically on-par with the tested Canon and the new stabilized version is said to be slightly better. Both Sigmas feature sonic drive AF, too. If one can live without sonic AF, Tamron's version may be the sharpest one of them all, Canon or not. However, with the lower prices, one loses the weather sealing offered by the Canon. Then, if you don't mind going for out of production lenses, there is the Tokina 80-200 f2.8, which is built so well that it could probably withstand a nuclear explosion. Just be sure to get the inner focusing, AF/MF clutch featuring, gold-banded “PRO” version for vastly improved AF over the one I tested already.

Value: 2/5
Now, I know I may take some heat for this, but the original Canon 70-200 f2.8L IS, while not a bad lens in itself, is a little underwhelming when considering its price point. First of all, when paying $1,600+ for a lens, one can reasonably expect top-notch performance wide open, which this lens does not deliver. If you can get by with f4 (where the lens is razor sharp), save some money and get the razor sharp right from the get go 70-200 f4L IS, which sells for $600 less. If you absolutely need f2.8, IS, and weather sealing, well, there's the superior “II” version, which is great right from f2.8. Then there are the better (in some respects) third-party alternatives. Lastly, when considering that this lens is out of production and service may be limited, what do you get? An over-priced white elephant, sorry.
Conclusion: 3.75/5
Canon's 70-200 f2.8L IS was, in its day, the best thing going for the photographer who demanded a versatile lens. Come 2011, the ship has sailed and there are better alternatives on the market from both Canon itself and third party manufacturers. Still, the lens has a lot going for it, namely build quality, USM, and, for the most part, good optics. However, it does have an Achilles Heel: sharpness at f2.8, which, for some, could be a deal breaker when considering the price. Another thing to consider is that, now that it is an out of production model, there is no guarantee that parts will be available should the lens break. Would I recommend it? No, for what it is at f2.8, the price is just too high, especially considering the alternative models and the fact that it is now out of production. However, should you come across a used one going for around $1000 or less, I'd give a cautious thumbs up, just hope that the AF motor holds together!




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Monday, December 12, 2011

Examiner for week of 12/4




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Saturday, December 10, 2011

This Morning's Total Lunar Eclipse: First Photos


As anyone who's even remotely interested in astronomy knows, this morning brought, for some, an 'impossible' total lunar eclipse. Unfortunately, owing to my living in the Eastern United states, I wasn't able to see either the partial, let alone total phases. In the end, it would have been a moot point as the clouds obscured the Moon, anyway. However, for people living in the Western United States who were lucky enough to have clear skies, some wonderful photo-ops abounded this morning. After all, it's not too often that you get to partner an eclipsed Moon with the famous Moon illusion.

Now, despite only a few hours having elapsed since the eclipse itself, the web is already starting to get flooded with pictures of the event.


Some good galleries can be found here:
Space.com
Spaceweather
Earth & Sky
Huffington Post
Thai Visual



Needless to say, there will be many, many more galleries popping up in the coming hours, so keep your eyes open!


My Eclipse Series
Start to finish eclipse photo gallery


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Friday, December 9, 2011

Total Lunar Eclipse Tomorrow Morning



Totality from a 2008 total lunar eclipse.

There is going to be a total lunar eclipse tomorrow morning that will be visible, at least partly, for most of the United States.


The eclipse's visibility.

As you can see, the Eastern United States will get virtually no eclipse at all, unless you consider the barely visible penumbral stage part of the eclipse. For people living in the EST meets CST area, you will be able to see a brief part of the partial phases at moonset. The farther West you live, the more you will be able to see, with people on America's West Coast being able to see just about all of totality and, in addition, the rare phenomenon, of senehelion, wherein the eclipsed Moon and Sun are visible in the sky at the same time thanks to the refraction of light caused by the atmosphere.



Photographing the eclipse:
Through a telescope
With a dSLR
With a cheap pocket cam

Pictures
Start to finish eclipse photo gallery



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Wednesday, December 7, 2011

Nikon D700 Running Review: Automatic White Balance


In photography, probably the second most vital thing to making a good picture (after being in focus) is the white balance (WB), which amounts to color tone brought upon by light source. So, what does that all mean?

Through millions of years of evolution, the human eye has adapted so that it can adjust to different light sources so that any given color, say white, always appears its true color no matter what the lighting condition/source is. Example: incandescent lighting has a low temperature of about 3000K while shady areas on a sunny day reflect light at around 8000K. Result: if you set your camera to the wrong WB, the color cast will be completely wrong.
Back in the film era, you had to use different color lens filters to get correct WB as different light sources have different temperatures. In the digital age, you can set your WB in the camera, but one is more likely to forget now as in the past because way back when, you couldn't help but notice what color filter was on your lens as you looked through the viewfinder! Result: a lot of pictures shot under the wrong WB setting. I know, I've done it and you've probably done it too.

Fortunately, there is a way to avoid having to constantly worry about the WB: the auto WB setting, which, in the case of the D700 uses Nikon's 1005 segment RGB sensor to measure the light source. Unfortunately, the auto WB function's evolution, unlike the eye's, is only a few years old, which means that the technological systems are anything but perfected. So, how does the D700 do in auto WB?

Answer: pretty darn good.

Under most settings, feel free to leave the D700 in the auto white balance setting as there is really no problem with the color casts produced. Sure, there may be a slight color difference in some situations, but they are always so minor that I personally wouldn't bother with changing the WB manually.

Auto white balance in sunlight.


 AWB in fuorescent lighting



AWB with flash (top).
Oh yes, the D700's built-in flash in no whimp, either.


 AWB in shade.



AWB under cloudy skies.



AWB in mixed light (incandescent and Sun)

Now I've shot with a lot of digital cameras and, so far, the most challenging lighting condition in which to get an accurate WB result in auto mode was under incandescent (tungsten) lighting. So how does the D700 do here?

Answer: it's the best I've ever used.

To this point, just about every single camera I've ever shot with, with exception of the Coolpix s550, also a Nikon (coincidence?), has failed to consistently meter a color temperature cool enough under incandescent light. Result: a very warm-looking picture with a deep orange/orange-yellow color cast to it. Needless to say, when using these cameras (which were good in every other lighting condition), I always set the WB to incandescent when shooting under such lighting. The D700? It's a heck of a lot better than anything else I've ever used. In practice, the D700 under incandescent lighting may produce a slightly warm image some of the time, but nothing truly objectionable. Yes, the dedicated incandescent setting produces cooler image (too cool in some lighting), but the D700's auto WB under incandescent lighting is the best thing I've ever seen. As a side note, I'd love to see what the new D7000 does as it has an all-new meter with over twice the sensors the D700's does, my guess is that it will be even better.

AWB under incandescent lighting.


As a last note to the WB settings in the D700, you can adjust them. By going into the shooting menu and selecting 'White Balance,' you can adjust the exact level of compensation the camera makes at each setting by altering the shades of Green, Blue, Amber, and Magenta. Result: you can fine tune the WB to your specific shooting conditions if so desired. For me, I may want to play around with the incandescent setting by shifting it a little to the blue in order to get a slightly cooler image under tungsten lighting.



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Tuesday, December 6, 2011

Examiner for Week of 11/27




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Thursday, December 1, 2011

Ancient American Astronomy, Part 1: The Moundbuilders

The New World: a place long thought to be a world of largely uncivilized wilderness upon the arrival of the first European explorers in around the year 1500. However, as the explorers pressed inward, they came across the traces of past, high civilizations and even a few that were still flourishing as the culmination of Native American civilization. .

In short, the civilizations the first European explorers encountered upon their arrival in the New World were the last in a long line of peoples to inhabit North America starting with the migration across the Bering Land Bridge before it was cut off by the rising seas following the end of the last Ice Age in around 10,000 B.C. Following the land free of ice down from Alaska, through Canada, and into what would eventually become the Continental U.S., these people fanned out across the vast expanse of land and were creating permanent settlements by 8,000 B.C. Unfortunately, as only the Maya developed writing (some of which scholars still can't understand), we are left with only artifacts and records from the first Europeans as to what the cultures that dominated the continent were once like. Obviously, with thousands of years of history before around 1500 A.D., there are a lot of unknowns, and educated guesses.
So, starting in North America, we will attempt to trace the astronomical legacies of the earliest Americans.

Some of the mounds are over 60 feet tall.

The first major group of peoples to be addressed are collectively known a the Moundbuilders, whose civilization was centered in the area of the Ohio and later Mississippi Valleys. However, as the general name implies, there is a lot more to the Moundbuilders than one group of people. Their dominance stretching from about 1000 B.C. to the arrival of the Europeans in around 1500 A.D., the Moundbuilders were actually a diverse group of people with a continually evolving culture. Despite the changing centuries, though, these people left quite an astronomical legacy in piles upon piles of soil.


Early rendering of the Great Serpent Mound.

Of all the mounds build in the early stages of the Moundbuilder civilization, the Great Serpent Mound, Located in Adams County, Ohio, is the most mysterious. At nearly 1,400 feet long, the Great Serpent Mound is the largest effigy (animal-shaped) mound in the world. Making the whole structure more mysterious is the fact that no one knows who built it, when, or why. However, at least for the last part, there are some possible guesses.


The Great Serpent Mound from the air.

Naturally, with all of its undulations, some people believe that there are astronomical alignments to be found within the Serpent's coils. For instance, there is the thought that the head of the snake points toward the Summer Solstice Sunset. In the main body, some think that the coils could be representing solar and/or lunar movements throughout their well-known cycles. On the other hand, other experts believe that these alignments are merely coincidental and that the giant snake was not built with these in the plans as there is not a single straight line on the outline. Either way, the Great Serpent Mound is and will remain a mystery.

The Octagon

Onto another Ohio earthwork, this one almost certainly with astronomical alignments that are not by chance. The Octagon is an acres-large geometric earthwork in Newark, Ohio that consists of a giant circle connected to, guess what, a huge octagon. Although no one can pin down an exact date for construction, it has been determined by looking at objects in the same strata that the Octagon was built by the Hopewell Culture, which flourished from around 200 B.C. to 500 A.D. In the 1980s, scientists decided to analyze the Octagon in the thought that they would find solar alignments. Unfortunately, no solar alignments were found. However, several lunar alignments, some of amazing precision, came to light.
First up, the main axis. Connecting the circle and octagon is a narrow lane with earthen banks on either side. It just so happens that this avenue points right at the Moon's northernmost rise of its 18.6 year cycle. Four other sides of the Octagon point to the maximum Southern rise, minimum Northern rise, maximum North set, and minimum Southern set. Obviously, with all the straight lines in the Octagon (versus all the curves in the Great Serpent Mound), chances are that the builders of the Octagon were intentionally trying to reflect the Moon's movements on Earth. In all, a pretty remarkable achievement for the time. However, things get better: the Octagon has a twin.


The High Banks Earthworks.

Located about 55 miles away in Chillicothe, Ohio, there is another earthwork called the High Banks Earthwork. In reality, it could be called the Octagon 2 as the two sites are virtually identical in layout (preservation is a very different story, though).

                                   

The supposed Great Hopewell Road.

On top of this, there is another amazing probability linking these two far flung (in the time of construction) sites: a road. Starting at the Octagon, remnants of a road 200 feet wide with earthen embankments for boundaries have been found leading out 6 milers toward Chillicothe. In the intervening miles between the two sites, more probable remnants of the “Great Hopewell Road” have been found, largely due aerial infrared photography that can detect changes in soil density) always parallel earthen banks 200 feet apart running on a direct line between the 2 sites.


Sunwatch Village, last astronomical achievement in the Ohio Valley.

After the decline of the Moundbuilders in Ohio, the culture would shift in focus to the Mississippi Valley (more later), but the astronomical achievements of the people in what is now Ohio were not at an end.

In Dayton, Ohio, a farming community was so in-touch with the sky, particularly the movements of the life-giving Sun, that they designed their whole settlement around solar motions. Appropriately called Sunwatch Village, the ancient settlement from around 1000-1500 A.D., originally excavated as a salvage operation, has now been fully restored to as original a condition as is possible after scholars realized its importance. Centered around tall posts in the ground, the Sun at various days will produce line of sight equinox and solstice alignments directed toward prominent buildings in the village. By looking at later constructions in the Americas, Sunwatch Village, though not overly spectacular in itself, was the start of a new trend of building to astronomical alignments that reflected the heavens' ever-growing influence on life as the old hunter-gatherer ways gave way to settled agriculture, which required precise timekeeping.


Monk's Mound in Cahokia. 

Moving to the South and West, the Moundbuilder culture reached its apex in the area of modern St. Louis at a city named Cahokia that flourished from around 650-1400 A.D. Unlike the ruins of other civilizations that were built in stone, the grandeur of Cahokia is largely unseen today except for one very prominent exception: Monk's Mound. Thought to be there center of the great city that once may have housed as many as 50,000 people, Monk's Mound is, at least in area, a third larger than the Great Pyramid in Egypt. While Monk's Mound may take all the limelight, another achievement reduced to post holes is the object of a lot of scholarly interest, too.


Artist's depiction of 'Woodhenge.'

Located to the West of Monk's Mound is a ring of ancient post holes. In all, there are over 100 holes in the ground in circles as large as 400 feet across. However, all of these posts together cannot represent a single structure, rather the evolution of a single site from a simple circle of 12 holes to t largest, most complex one that contains 48. Obviously, holes in the Earth were not always just holes and what historians think that all the post holes at Cahokia represent are the remains of circular rings of posts in the ground not unlike Stonehenge in England. In the interest of hands-on archeology, “Woodhenge,” the 48 post, 400 foot diameter version of the henge, has been fully reconstructed. So far, solstice and equinox alignments have been discovered and far more may await recognition.
For anyone looking at the dates, one cannot help but notice how the fall of the final Moundbuilder civilizations coincides with the arrival of the first European explorers. However, in contrast to what many would assume, the Moundbuilder culture was already in a sharp decline when the Europeans arrived and was not spurred on, as in Central and South America, by the Europeans themselves. In fact, Spanish explorers wandered into Cahokia in the early 1500s, a point in time where the once great city was nearly abandoned. No one knows why the great Moundbuilder civilization faltered around 1500, but the consequences of the mysterious downturn, namely the unsolved puzzles which tey left us with, are the consequence. Hopefully, with enough time, the mysteries of the Moundbuilders, astronomical and not, will finally be solved.

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