Stories tagged Scientific Inquiry

Dec
26
2009

GOCE Satellite: The Gravity field and steady-state Ocean Circulation Explorer
GOCE Satellite: The Gravity field and steady-state Ocean Circulation ExplorerCourtesy ESA
Can it be true? Yes, for a mere $5,544 dollars round-trip airfare to Greenland! In March 2009, the European Space Agency launched the Gravity field and steady-state Ocean Circulation Explorer (GOCE) into orbit around our planet, which is now transmitting detailed data about the Earth’s gravity. The GOCE satellite uses a gradiometer to map tiny variations in the Earth’s gravity caused by the planet’s rotation, mountains, ocean trenches, and interior density. New maps illustrating gravity gradients on the Earth are being produced from the information beamed back from GOCE. Preliminary data suggests that there is a negative shift in gravity in the northeastern region of Greenland where the Earth’s tug is a little less, which means you might weigh a fraction of a pound lighter there (a very small fraction, so it may not be worth the plane fare)!

In America, NASA and Stanford University are also working on the gravity issue. Gravity Probe B (GP-B) is a satellite orbiting 642 km (400 miles) above the Earth and uses four gyroscopes and a telescope to measure two physical effects of Einstein’s Theory of General Relativity on the Earth: the Geodetic Effect, which is the amount the earth warps its spacetime, and the Frame-Dragging Effect, the amount of spacetime the earth drags with it as it rotates. (Spacetime is the combination of the three dimensions of space with the one dimension of time into a mathematical model.)

Quick overview time. The Theory of General Relativity is simply defined as: matter telling spacetime how to curve, and curved spacetime telling matter how to move. Imagine that the Earth (matter) is a bowling ball and spacetime is a trampoline. If you place the bowling ball in the center of the trampoline it stretches the trampoline down. Matter (the bowling ball) curves or distorts the spacetime (trampoline). Now toss a smaller ball, like a marble, onto the trampoline. Naturally, it will roll towards the bowling ball, but the bowling ball isn’t ‘attracting’ the marble, the path or movement of the marble towards the center is affected by the deformed shape of the trampoline. The spacetime (trampoline) is telling the matter (marble) how to move. This is different than Newton’s theory of gravity, which implies that the earth is attracting or pulling objects towards it in a straight line. Of course, this is just a simplified explanation; the real physics can be more complicated because of other factors like acceleration.

Albert Einstein
Albert EinsteinCourtesy none
So what is the point of all this high-tech gravity testing? First of all, our current understanding of the structure of the universe and the motion of matter is based on Albert Einstein’s Theory of General Relativity; elaborate concepts and mathematical equations conceived by a genius long before we had the technology to directly test them for accuracy. The Theory of General Relativity is the cornerstone of modern physics, used to describe the universe and everything in it, and yet it is the least tested of Einstein’s amazing theories. Testing the Frame-Dragging Effect is particularly exciting for physicists because they can use the data about the Earth’s influence on spacetime to measure the properties of black holes and quasars.

Second, the data from the GOCE satellite will help accurately measure the real acceleration due to gravity on the earth, which can vary from 9.78 to 9.83 meters per second squared around the planet. This will help scientists analyze ocean circulation and sea level changes, which are influenced by our climate and climate change. The information that the GOCE beams back will also assist researchers studying geological processes such as earthquakes and volcanoes.

So, as I gobble down another mouthful of leftover turkey and mashed potatoes, I can feel confident that my holiday weight gain and the structure of the universe are of grave importance to the physicists of the world!

Dec
08
2009

Poop with flies: you always manage to find a few of these guys on the pile.
Poop with flies: you always manage to find a few of these guys on the pile.Courtesy PKmousie
Poop. Poop. Poop. Poop. There. Have I got your attention? Of course, who can resist a story on poop? It is such a widely discussed topic with a vast array of monikers. Probably not a decent topic of conversation for invited guests or the dinner table, but it does get its chat time. Despite the disgust that it truly is, there is a curious fascination with the whole matter. It can tell you about your health, especially if you have the runs. It can tell you if you’ve been chewing your food well, or if you need to lay off the cheese. If you are a proper biologist, you’ve probably bent down and touched it or even broke it up to examine what passed. Certain scientists, such as Scatologists pursue the study of scat (poop) as a means to tell us more about a certain animal’s habits. If by the Fates, a poo survives intact and becomes old enough to fossilize, then we would call it a coprolite. Coprolites have been recovered from dinosaurs, ancient whales, fish, and prehistoric mammals to name a few.Coprolite: one very old poo
Coprolite: one very old pooCourtesy AlishaV

Recent news from BBC detailed a story about scientists studying the ancient droppings from mammoths. Well sort of. The researchers were examining mud deposits from a lake for fungal spores that are produced in large herbivore dung (mammoth poo). Their research concludes that the extra large mammals of the recent past experienced a slow and steady decline starting about 15,000 years ago. This flies in the face of the current prevailing theory, that an asteroid impact about 12,900 years ago caused global upheaval, world spread wildfire, and then abrupt extinction of the mega mammals. The asteroid theory had already been under assault by lack of evidence in soil samples. Samples taken all over the continent in soil cores extracted from peat bogs and lake bottoms.
Mammoth: artistic re-creation
Mammoth: artistic re-creationCourtesy ecstaticist
Was early man really responsible for the start of the downfall of the mammoth? I think undoubtedly we had a hand in their fate, but the answer is most likely multifaceted. Taking a closer look at the dung heaps of the past may well continue to give us a better picture of paleohistory. Just watch where you step!

mammoth dung story

mammoth comet story

Nice story on a recent find of a baby mammoth"

General Mammoth info
http://www.museum.state.il.us/exhibits/larson/mammuthus.html
http://www.ucmp.berkeley.edu/mammal/mammoth/about_mammoths.html

Dec
02
2009

Phil Jones, the director of the Climate Research Unit (CRU) at the University of East Anglia in Great Britain, is stepping down from his post pending an investigation. Jones is at the center of a controversy over the CRU’s activity. E-mails released on the web seem to indicate a variety of improper behavior, including manipulating data, destroying data, refusing to share data with other researchers, and trying to prevent researchers with other theories from getting their results published. Jones has not been officially charged with any wrong doing at this point. But until the controversy is settled, he will relinquish his position as director of the unit.

Meanwhile, Pennsylvania State University has launched a review of Michael Mann, a University scientist also involved in the controversy and author of several of the e-mails.

We discussed the controversy in more detail in this post, with updated information in the comments.

Nov
29
2009

Wadena county, Minnesota
Wadena county, MinnesotaCourtesy wikipedia image
During the summer of 2009, I had the opportunity to spend four weeks in the field doing actual scientific investigation. From mid-June until mid-July, I was a participant in the University of Minnesota's archeology summer field school run by Professor Kat Hayes. The mission of the field school was to attempt to confirm the presence of a European footprint in this remote part of what would become a young Minnesota territory.

The site of Little Round Hill is located in Wadena County, Minnesota, part way between the towns of Staples and Wadena. Currently, it is part of a county park system. Located at the confluence of the Crow Wing River and the Partridge River, Little Round Hill is believed to be a historical site from the early French fur trading days.

The story goes something like this. In the mid- 1800's, William Warren wrote an account of Ojibwe life in a growing Minnesota territory. In his work, Warren interviewed an elderly Ojibwe man. This elderly man recounted days spent at a fur trading encampment while he was just a young boy. The encampment centered around the dwelling of a French fur trader and his handful or so of Coureur-des-bois . Staying with this trader were around ten Ojibwe hunters and their families. According to the account, Little Round Hill became the focus of contention between rival bands of Ojibwe and Lakota hunters. By oral recollection, there was an incident of more than 200 Lakota warriors approaching and attacking the outpost. The Frenchmen and Ojibwe held the attackers at bay with guns while barricading themselves into the main encampment. The attackers, with only a few guns and armed mainly with bow and arrow for projectiles, were unable to overcome the defenses and eventually retreated.

The site itself had been recognized for its historical implications for quite some time. For years, local residents have pondered that possible remains may lie buried at the Little Round Hill location. In 1992, Douglas Birk conducted an initial survey of the site. While artifact remains spanning several centuries were recovered in his explorations, they didn’t produce evidence of any of the structures described in the oral account.

The summer of 2009 excavations started out with a whimper. Rain and uncooperative weather hampered our beginning efforts. As the clouds passed, the field crew opened a handful of excavation pits and began searching for artifacts. The results were productive and encouraging. Items of distinct European influence started to appear in most of the test areas including musket balls, cut pieces of finished copper, small trade beads, a couple pieces of worked metal (still of undetermined nature), a few pottery shards and even a small ring (possibly silver).
musket ball: the first such item found and it came from my pit!
musket ball: the first such item found and it came from my pit!Courtesy K.Kmitch

Additional materials such as a stone arrowhead, lithic debris, and animal bones both broken and charred were recovered. After a month of work and close to a dozen open explorations, much more habitation evidence was revealed. While no sign was uncovered of the fortifications mentioned in the oral account, at least three of the excavation points did expose strong support for likely hearth locations. These may have been centered near the possible dwellings of the occupants.

Alas, the season of excavation is a short one in Minnesota. After a month of work, the crew retreated home with bags of evidence in hand. During the 2009-2010 academic year, the materials are being analyzed and cataloged at the University of Minnesota. A full report on the findings is expected this coming spring. While the preliminary data does not show conclusive evidence of the mentioned encampment, enough material was recovered to warrant further investigation. Plans are to return to the site next summer to resume excavations and expand exploration of the area. I, for one, can not wait and hope to have my hand in the dirt once again come summer 2010.

Nov
25
2009

A controversy is brewing in the world of climate science. On Thursday, November 19, a Russian website posted over 1,000 e-mails and almost 3,000 data files from the Climate Research Unit (CRU) at the University of East Anglia in Great Britain. The CRU is one of the major centers of climate research in the world, and provided much of the data for the United Nation’s Intergovernmental Panel on Climate Change (IPCC) report.

The e-mails, written by some of the leading climate scientists in Britain and America, seem to suggest some very disturbing behavior:

* manipulating climate data to fit pre-existing theory
* refusing to share data with peers to check for accuracy
* circumventing legal requirements to release information, and even deleting some of it
* pressuring journals to reject papers that don’t fit the theory, and even pushing editors out of their posts

The story has been covered by the New York Times, the Washington Post, and the Wall Street Journal. You can find a good summary of how the story broke on Pajamas Media. Blogger Bishop Hill is keeping a running list of the most controversial e-mails. And, if you just want a quick summary, there’s “Three Things You Absolutely Must Know About Climategate.”

The University has acknowledged that its system was illegally hacked, but cannot vouch for the authenticity of every item. (There is also some suggestion that the information may have been leaked by an insider.) Several authors and recipients have verified some of the e-mails as genuine; as of this writing, none of the messages have been refuted. The sheer amount of data – over 170 megabytes – suggests this is not a hoax, though many authors have cautioned that it would be easy for a prankster to slip a few bogus e-mails in with all the legitimate ones.

But, assuming the e-mails are genuine, what do they tell us?

The alleged non-compliance with the Freedom of Information Act is a legal matter. We can say nothing about it, other than no charges have been filed, and everyone is presumed innocent until proven guilty.

The e-mails which seem to describe fudging the facts to fit the theory have received the most attention. It would be disturbing indeed if scientists at a major research institute were falsifying data. Though only a handful of papers have so far been implicated, if the allegations are borne out it would cast a pall over these scientists’ other work, their collaborations, and even work done by other scientists which was based on the disputed data.

These particular e-mails have also received the strongest defense. The authors, and even some third-party observers, maintain that the messages are being quoted out of context and misinterpreted, and that some phrases which appear damning actually have innocent explanations. (To date, there has been little reporting on the much larger, much more complex data files, which may shed light on this issue.)

Perhaps most disturbing, from a science standpoint, are the withholding of data from outside researchers, and the pressure put on journals to not publish dissenting views. Science absolutely relies on vigorous, evidence-based debate. If the evidence is not made available, the debate cannot take place. Furthermore, proponents of human-caused global warming have long criticized dissenters for not publishing their papers in peer-reviewed scientific journals. However, if it turns out that those journals were controlled by proponents who actively kept dissenters out, then the argument loses merit.

On this last point, global warming proponents and dissenters agree. Writers such as Megan McArdle and George Monbiot argue that the case for human-caused global warming remains strong, but that subverting the peer-review process blocks scientific progress and is a major blow to credibility.

So, what next? Politicians in Britain, Australia and America are calling for investigations. Climate studies are funded with taxpayer dollars, and lawmakers pass legislation based on the information the studies provide. Governments have an obligation to make sure it is accurate. And, as noted earlier, the easy work of reading the e-mails has largely been done. The more difficult task of sifting through the data files will take longer. Already, some programmers are questioning the computer models CRU developed to predict climate. If there are more updates, we’ll be sure to post them here.

Nov
20
2009

Of course, some dinosaurs may not be missing--just hiding.: Many species adopt camouflage to blend in to their environments.
Of course, some dinosaurs may not be missing--just hiding.: Many species adopt camouflage to blend in to their environments.Courtesy Elston

Looooooong time passing....

Seems like some of them were never here to begin with. Over the years, scientists have named about 700 different species of dinosaurs. But a recent study indicates that perhaps as many as a third of these were phantoms—specimens that were given distinct names despite actually belonging to another, well-known species.

For example, Torosaurus is now thought to be just a fully mature version of Triceratops. At the other end of the age scale, Nanotyrannus is considered by some to be just a juvenile form of the famous Tyrannosaurus rex.

Why the changes? Well, identifying species is hard, even under the best of circumstances. With fossils, it’s especially tricky. You often only have one specimen to study, not dozens or hundreds as with living creatures. You can only see the fossil’s bones, not the full creature. And, most important, you only have the dead body—you can’t watch the living creature to see how it changes as it grows. (Dinosaur bones, it seems, are extremely malleable and prone to change shape as the creature matures.)

But don’t be too hard on the poor paleontologists. Other scientists have this same problem. Last year, it was reported that over 30% of all living marine creatures had been misidentified, and for the same reasons. An individual (or small group) was slightly larger than normal, or slightly smaller, or a slightly different color, or came from a different location—enough to lead the scientist to classify it as a new species, when in fact it was already a member of an established species. If taxonomists can make that many mistakes with living creatures, we shouldn’t be surprised that the dinosaur family tree will need a little pruning.

Aug
24
2009

This is not BEAR: It's how I think of BEAR.
This is not BEAR: It's how I think of BEAR.Courtesy JGordon
Have we never talked about the uncanny valley on Science Buzz? I searched for the term, and got nothing. (Although… I’m beginning to suspect that my computer doesn’t accept voice commands. “Computer, display LOLcats,” gets me nothing, and I know that there are LOLcats out there.)

So… the uncanny valley. It has to do with robots, and human-simulation thingys. It’s like… like… well, here’s an example:

Think about factory assembly line robots—big arms, repetitive movements… it doesn’t do much for you, does it? They’re just boring ol’ machines.

Now think about R2D2, Star Wars’ trashcan robot. Beep beep, whistle! Cute, huh? He rolls around, and does sassy things we can’t understand, and we know he’s a robot, and he’s pretty likeable.

Now think about Johny 5 from Short Circuit. He can talk, he’s got a face, and expressive eye-flaps. And we still kind of like him, despite the attitude. (Great, you can read fast. Clean my kitchen before I have you recycled, robot.)

Now think abut C3PO, Star Wars’ deeply uncomfortable, shuffle-gaited robot. He’s pretty much human shaped, he speaks human (with an accent too…), and he’s clearly grappling with some of the same personal identity issues we real humans deal with. And… he’s just a little bit creepy, isn’t he? He’s like us, but not like us… How do we deal with this goldbot?*

And then there’s the “Simroid,” the Japanese robotic monstrosity used for dentist training. See the Simroid:

Clearly Lady Simroid has discovered what it means to be human, and she is, appropriately, horrified. And it doesn’t help that her existence is limited to sitting in a chair and having dental students see what hurts.

But, see, robots like the Simroid, in their appearance and limited behavior, are quite like humans. And it’s weird! They make us uncomfortable. So like us, but they’re absolutely missing the piece that makes a person a person. Brrrr

And then, moving on, we have healthy, living humans. Or maybe Blade Runner replicants. And they aren’t so weird any more. We’re back up to something we’re comfortable with.

It’s the Simroid point on this scale where the familiarity/comfort level takes a huge dive. That’s the uncanny valley.

(Another way to think about it might be cartoons. Stick figures. Disney’s Aladdin. Toy Story. The Polar Express movie adaptation. Pirates of the Caribbean. Which of these are you least likely to see on a poster in a kid’s bedroom? Well, maybe stick figures, but do you see what I’m getting at?)
See the dip in the graph?: That's the uncanny valley. It's full of zombies and simroids.
See the dip in the graph?: That's the uncanny valley. It's full of zombies and simroids.Courtesy Smurrayinchester

There are different theories as to why objects in the uncanny valley creep us out so much. The remind us of dead things. (Like zombies!) They are similar enough to us that, on a biological level, we perceive them as a threat (because a genetically similar creature is more likely to pass diseases to us, I guess), and so we feel revulsion towards them. Or they’re no longer like robots, but when we judge them on the human scale, they come up disturbingly lacking. Basically, they’re weird.

So, when you’re building your humanoid, you have to decide early on where you’re going to shoot for on the uncanny valley scale. If you aim too high, you may end up dooming your creation to the same hate we have for ventriloquists’ dummies. (In my opinion, you should probably set your expectations somewhere around R2D2, unless you’re making a baby. And even then…)

Enter the military-funded “Battlefield Extraction-Assist Robot,” or BEAR. BEAR was designed to be able to rescue wounded people in combat areas, and to do heavy, potentially dangerous tasks. It’s basically some big treads and a torso with arms, and each new version is a little stronger, and more nimble and damage resistant. And the newest versions have bizarre teddy bear heads, apparently because that’s the sort of thing that’s reassuring to an injured soldier.

So where does this fall on the uncanny scale? We like teddy bears. But teddy bears are usually soft and fuzzy, not six-foot-tall human-torsoed robots, able to dead lift 500 pounds. Also, their dark lifeless eyes aren’t usually set in hard, urban camo faces. For me, at least, a face like that seems to promise physical dismemberment with utter, robotic detachment (pun intended, I guess?).

Am I alone? Am I relating too much (but not enough) to the BEAR? How do y’all feel? Anything else in the uncanny valley that you feel deserves a shout out for its creepiness? Let’s have it.

*I’m aware that R2D2 and C3PO are supposed to be spelled out phonetically. I won’t be doing that. Ever.

Aug
17
2009

This is all assuming the zombies don't have guns: But they rarely do. See Day of the Dead (original version) and Land of the Dead for exceptions.
This is all assuming the zombies don't have guns: But they rarely do. See Day of the Dead (original version) and Land of the Dead for exceptions.Courtesy Suitov
Remember in 8th grade, when you were taking geometry or pre-calc or whatever, and some cleverboots in the back row asked the teacher when anyone was every likely to use math in real life? Your teacher probably said something like, “Do I have to shake the answer into you, numbskull? You’ll use it every day! What if you want to figure out the rate of wear on your tires based on circumference? What about when you want to figure out the height of your favorite tree, using only the length of its shadow?” And because everyone involved could see the hollowness of this answer, you went home feeling a little darker.

But, see, what your lousy teacher should have said is that when the zombie apocalypse comes, math is what’s going to drag us out of that corpse-filled scenario and into a brighter, infection-free future. Because, when it comes to zombies, math is the real weapon.

JK, of course. Claw hammers and chainsaws will still be the real weapons. No getting past that—even the trickiest math problems will hardly destroy the brain, much less sever a spinal cord. But mathematical models will provide a strategy for survivors.

Mathematical models for vampire scenarios are old hat. They’re old, boring hat, in fact, on account of how people can’t agree about the methodology, and because vampires aren’t that great in the first place. But a practical zombie model is making the rounds in the popular press, because this is the sort of thing we need to know.

Taking into account infection rates, and the relative numbers of “suseptable,” “zombie,” and “removed” individuals, the model confirms what we have long suspected: that a zombie outbreak would suck. The model is, of course, much more complicated than this, and it has lots of fun little symbols and graphs, but that’s the long and short of it.

However, the model does leave room for hope. Putting victims into quarantine could eradicate the infection, but only under ideal circumstances (i.e., not in the real world), and a while a zombie cure could ensure the continuing existence of humanity, survivors would need to coexist with zombies. The remaining solution, and the only practical one, it turns out, is the old fashioned one: head smashing. As the paper puts it, “only sufficiently frequent attacks, with increasing force, will result in eradication.”

We’ve got to hit the zombies where they live. Or where they undead-live. Or whatever. The point is that when the time comes (any day now), we have to take the fight to the zombies, and we have to do it fast. So prepare your bite-guards and blunt instruments, and put them next to your fire extinguisher and emergency blanket. Be a survivor.

Here’s the original paper in pdf format.

A quick note: To all of you who are thinking, “Puh-leaze, JGordon. Zombies are played out like Super Bowl XLIII,” I respond with a puh-leaze of my own. I say y’all are the ones played out, played out like Mario 3, and I think y’all should check yourselves and just go watch Transformers 2, or whatever it is you people are into.

Jul
20
2009

Super Solar Ring: ...but remember, don't look directly at it or you WILL GO BLIND!!!
Super Solar Ring: ...but remember, don't look directly at it or you WILL GO BLIND!!!Courtesy Incredible India

Get ready, because one of Newton’s laws is about to be tested. A little thing called gravity is going into question during the total solar eclipse on July 22nd.

I’m sure most of you have heard of or know what a solar eclipse is. If not, here’s a refresher: “A solar eclipse occurs when the Moon lies between the Sun and Earth, casting its shadow on our planet. Depending on the location of the observer on the Earth’s surface, the observer may see a total solar eclipse, a partial solar eclipse or none at all. If the observer is lucky enough to be located in a position where the moon’s umbra contacts the Earth they will witness a total solar eclipse of the sun.”

Unfortunately for those of us in St. Paul, the only way for us to see the total solar eclipse would be to buy a one-way ticket to the eastern hemisphere. The path of the eclipse will start in eastern India and end about 2,000 miles south of Hawaii. During which it will be visible for nearly 6 minutes in China, and that’s where Newton steps in (not literally of course).

Researchers at the Chinese Academy of Sciences are about to test the controversial theory that gravity drops slightly during a total eclipse. Originally observed in 1954, the French physicist Maurice Allais noticed erratic behavior in a swinging pendulum when the eclipse passed over Paris. The shift in direction of the pendulum’s swing suggests a sudden change in gravitational pull. Though tests have occurred since, nothing has been conclusive.

The best chance to prove the gravity anomaly is this Wednesday during the longest eclipse duration of the 21st Century. This is why Chinese geophysicists are preparing six different sites with an array of highly sensitive instruments to take gravitational readings during the total eclipse. The head geophysicist Tang Keyun states, "If our equipment operates correctly, I believe we have a chance to say the anomaly is true beyond all doubt."

Jul
18
2009

Apollo 14's remains: Even higher resolution images will be coming from the LRO, when it enters a lower orbit soon.
Apollo 14's remains: Even higher resolution images will be coming from the LRO, when it enters a lower orbit soon.Courtesy NASA
The Lunar Reconnaissance Orbiter (LRO) is NASA's satellite orbiting the moon right now to give us all a much more detailed picture of our nearest space neighbor. Just in time for the 40 anniversary of the moon landing, the LRO has passed by several of the Apollo mission landing spots. In the best photograph you can actually still see the footsteps between the remains of the landing vehicle and the scientific instruments. It's so cool to see the path worn into the lunar landscape still there on this windless world.