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for March, 2009.
Well, since we did medicine last week I thought we’d move to a subject that’s near and dear to my heart: space research. One of the things I love about my field is that it literally changes every day. What we believe today may definitely NOT be what we believe next week. And one of the biggest fields that’s changing every day is planetary science. That’s because we still have several intrepid robot explorers that are giving us daily reports about the conditions on Mars and Saturn.
The robot Cassini is in orbit around Saturn and we’ve learned more about Saturn and its many moons in the last four years than we learned in the previous 400. We’ve found new moons, seen a half-black, half-white moon (Iapetus) up close and learned that it has a 12-mile high mountain ridge around its equator. But one of the major objectives of the Cassini spacecraft was to explore Titan, the second largest moon in the solar system (after Jupiter’s Ganymede) and the only moon to have a substantial atmosphere.
NOT LIKE EARTH!
Cassini landed a probe on the surface of Titan. The surface had always been a mystery until Cassini because the atmosphere is opaque and we can’t see the surface from Earth.
The probe took many pictures in its spiral down to the surface and saw a landscape that was surprisingly Earth-like. There were mountains, cliffs and what appeared to be rivers flowing to large flat areas that looked suspiciously like large lakes or seas. But even though the surface looks like Earth, we knew it couldn’t be, because the average temperature on Titan is -290 degrees!
Interestingly enough, at those temperatures, water ice, as we know it, doesn’t exist. The only reason we have life here on Earth is that, unlike virtually any other compound, our kind of water ice floats on liquid water. If that weren’t true, the oceans would have frozen solid from the bottom up and we wouldn’t be here.
But at -290 degrees frozen water isn’t ice as we know it. Ice at the temperatures on Titan is water rocks; just like the familiar rocks here on Earth, but made of water. These water rocks would NOT float on liquid water (if there were any on Titan) they would sink like, well, a rock.
We are still studying the surface of Titan with radar and we’re discovering that the surface changes. Although scientists are still debating this, it appears there are volcanoes on Titan. They’re called cryovolcanos, which basically means ‘volcanoes’ much colder than you ever dreamed possible. And if the rocks that make them are made of water what are these volcanoes erupting? That’s right! Molten water!! Lava that is, in fact, water. They are probably also erupting liquid methane and ammonia. Certainly NOT Earth-like at all.
Is there life on Titan? We still don’t know, but we need to give up on the idea that life must be as we know it. The aliens will NOT be humans wearing monster costumes or sporting strange hairstyles.
A moon that erupts molten water. Strange indeed!
And now we’ll take a little trip from Saturn to Jupiter to have a look at the second biggest storm in the solar system and find out why it’s blushing.
A recent study has given new insights into why Oval BA, a giant anticyclone on Jupiter also known as Little Red, suddenly turned from white to red in a period of just a few months.
We all know about Jupiter’s Great Red Spot, a huge spinning storm that can be three times larger than Earth and has been on Jupiter’s surface for over 300 years.
A couple of years ago, I reported that a huge white spot had formed on Jupiter from a chain of white spot collisions that started way back in 1998. The large white spot that resulted was called Oval BA. Amateur astronomers reported a couple of years ago that Oval BA was beginning to turn red, but it wasn’t until April of last year that professional astronomers were able to image the impressive alteration of the second largest storm in the Solar System after the Great Red Spot (GRS).
The scientists that studied Little Red made an in-depth analysis of all the aspects regarding its history and evolution. The reddest color was concentrated in a ring around the spot’s center. But when the researchers calibrated images taken with the Hubble Space Telescope, they found out that Little Red didn’t actually change in red or infrared wavelengths. Instead, it became darker in blue and ultraviolet wavelengths, which made it look redder.
And the researchers didn’t limit themselves to data from Hubble. They also used images taken by the Cassini spacecraft on its way to Saturn as well as pictures taken by the New Horizons mission and computer models. They searched for possible causes for the color change, including alterations to dynamic, photochemical and diffusion processes.
Their conclusions? The most likely cause appears to be an upward and inward diffusion of either a colored compound or a coating vapor that may interact later with high energy solar photons at the upper levels of Little Red.
When they compared Little Red to The Great Red Spot, they found that the GRS is still redder than Little Red, most likely because it’s higher in Jupiter’s atmosphere, thicker and contains a higher concentration of the mysterious unknown chemical agents that give Jupiter its brownish-red color.
The scientists were able to rule out that the reddening was caused by any dynamic processes. They found no change to the strength of the “hurricane” and, although some changes in the circulation around the spot had taken place, the maximum wind speeds (which may range up to 250 mph or more!) were consistent with measurements previous to 2000 of Little Red or its white predecessors.
Their models also showed that the color change wasn’t caused by interactions of Little Red with the GRS, even though they were relatively close at the time. The flow around both vortices is so strong that it keeps the storms separate. They also ruled out the height of Little Red since it didn’t change; but there were large changes in the temperature gradient of the storm.
Bottom line? We STILL don’t know what causes the color, but we’ve ruled out several things that don’t. And that’s how science progress, you know. Ruling out one thing at a time that doesn’t fit what we actually observe. A slow process sometimes, but it works.
NOT ALWAYS ON THE LEVEL
One of the abiding ‘facts’ about our solar system is that virtually everything spins around the Sun on the same ‘table’. That ‘table’ is called the plane of the ecliptic and one of the things that made Pluto so unplanet-like is that its orbit is significantly inclined to the ecliptic plane. It doesn’t roll around on the same table as the planets.
Virtually the only things that humans routinely observe that don’t follow the ecliptic are the comets and an international team of scientists has found an unusual object whose backward and tilted orbit around the Sun may clarify the origins of certain comets.
In the first discovery of its kind, researchers from Canada, France and the United States have discovered an object that orbits around the Sun backwards, and tilted at an angle of 104 degrees – almost perpendicular to the orbits of the planets. This goes far toward proving that the comets exist in a large spherical cloud far beyond Neptune called the Oort Cloud.
The object is called 2008 KV42 and is made of icy rock. It’s also called a "trans-Neptunian" object since its orbital path is larger than that of Neptune. The object is roughly 30 miles across and about 3.5 billion miles from Earth.
We don’t normally look up or down in our solar system examination but the international research team has been carrying out a targeted search for objects with highly tilted orbits. Their discovery was made using the Canada-France-Hawaii Telescope in Hawaii, with fol
low-up observations provided by the MMT telescope in Arizona, the Cerro Tololo Inter-American Observatory (CTIO) four-metre telescope in Chile, and the Gemini South telescope, also in Chile.
The researchers had to use telescopes in both the northern and the southern hemispheres because 2008 KV42 would have been lost to view without the rapid tracking from the large telescopes in both hemispheres.
The discovery team is currently performing follow-up observations of 2008 KV42 to pin down its orbit with greater precision. They will then begin unraveling the archaeological information trapped in the orbit of this highly exceptional member of the trans-Neptunian population.
A near edge-on view of the solar ecliptic plane viewed from about 10 billion miles. This figure shows the orbits of Neptune (diameter 3 billion miles), Pluto, 2008 KV42 and 4 other ‘classical’ KBOs. Demonstrates the inclined nature of 2008 KV42’s orbit, when compared to other objects in the outer solar system. (Credit: Canada-France Ecliptic Plane Survey)
Volcanoes that erupt molten water, big red spots and strange visitors on a different plane. The solar system is full of wonder.
Cruise on over to the Deep Website at www.thedeepradioshow.com to learn more about space and many other topics. Enjoy!
Well, the medicine file is filling up fast so it’s time to take another excursion into the wonderful world of the human body and its functions. Our first story has great relevance here. I teach a course for teachers called Hands-On Science. In this class, teachers learn a little science connected with the presented activity, and then do the activity themselves so it’s easy for them to do these activities with their students.
All the presented activities have a ‘local’ spin. They use coconuts and Palo Maria nuts, teach about natural phenomena that can be observed only in the tropics like mangrove swamps and “The Day of No Shadows” or deal with cultural topics like carving Chamoru proas from soap bars.
One of the most popular activities with all the teachers is one called “How Sweet it Is” by Tom Terlaje. In this activity, teachers use the nutrition labels on snacks and soft drinks to determine how much sugar they contain. These amounts are measured out into zip bags with coded labels. The students then match the sugar bags with the empty snack bags and soft drink cans. The amount of sugar contained in common drinks and snacks is frightening. And that brings us to our first article.
HOW SWEET IT ISN’T!
A Princeton University scientist has presented new evidence that demonstrates sugar can be an addictive substance, that wields its power over the brains of lab animals in a manner similar to many drugs of abuse.
Professor Bart Hoebel and his team in the Department of Psychology and the Princeton Neuroscience Institute have been studying the signs of sugar addiction in rats for years. In previous studies, the rats he’s used have met two of the three elements of addiction. They demonstrated a behavioral pattern of increased intake and then showed signs of withdrawal. His current experiments show craving and relapse, the third element of addiction to complete the picture.
"If bingeing on sugar is really a form of addiction, there should be long-lasting effects in the brains of sugar addicts," Hoebel said. "Craving and relapse are critical components of addiction, and we’ve been able to demonstrate these behaviors in sugar-bingeing rats in a number of ways."
In a recent report, Hoebel showed profound behavioral changes in rats that, through experimental conditions, have been trained to become dependent on high doses of sugar.
Lab animals that were denied sugar for a prolonged period after learning to binge worked harder to get sugar when it was reintroduced to them. They consumed more sugar than they ever had before, suggesting craving and relapse behavior. Their motivation for sugar had grown. "In this case, abstinence makes the heart grow fonder," Hoebel said.
The rats drank more alcohol than normal after their sugar supply was cut off, showing that bingeing behavior had made changes in brain function. These functions served as "gateways" to other paths of destructive behavior, such as increased alcohol intake. And, after receiving a dose of amphetamine normally so minimal it has no effect, they became significantly hyperactive. The increased sensitivity to the stimulant is a long-lasting brain effect that can be a component of addiction.
Hoebel has shown that rats that eat large amounts of sugar when hungry, a phenomenon he describes as sugar-bingeing, undergo neurochemical changes in the brain that mimic those produced by substances of abuse, including cocaine, morphine and nicotine. Sugar induces behavioral changes, too. In certain models, sugar-bingeing causes long-lasting effects in the brain and increases the inclination to take other drugs of abuse, such as alcohol.
The researchers conducted the studies by restricting rats from their food while the rats slept and for four hours after waking. "It’s a little bit like missing breakfast," Hoebel said. "As a result, they quickly eat some chow and drink a lot of sugar water." And, he added, "That’s what is called binge eating — when you eat a lot all at once — in this case they are bingeing on a 10 percent sucrose solution, which is like a soft drink."
In experiments, the researchers have been able to induce signs of withdrawal in the lab animals by taking away their sugar supply. The rats’ brain levels of dopamine dropped and, as a result, they exhibited anxiety as a sign of withdrawal. The rats’ teeth chattered, and the creatures were unwilling to venture forth into the open arm of their maze, preferring to stay in a tunnel area. Normally rats like to explore their environment, but the rats in sugar withdrawal were too anxious to explore.
The findings are exciting, Hoebel said, but more research is needed to understand the implications for people. The most obvious application for humans would be in the field of eating disorders. "It seems possible that the brain adaptations and behavioral signs seen in rats may occur in some individuals with binge-eating disorder or bulimia," Hoebel said. "Our work provides links between the traditionally defined substance-use disorders, such as drug addiction, and the development of abnormal desires for natural substances. This knowledge might help us to devise new ways of diagnosing and treating addictions in people."
Sugar. Rats drank more alcohol than normal after their sugar supply was cut off, showing that the bingeing behavior had forged changes in brain function. (Credit: iStockphoto/Tobias Helbig)
So . . . sugar is probably addictive. That comes as no surprise to me and shouldn’t come as a surprise to any of you. Think about how many sugared sodas you drink every day! And our next story should also come as no surprise.
THE WAGES OF ANOTHER ADDICTION
The association between tobacco smoke and cancer deaths and NOT just lung cancer deaths has been strengthened by a recent study from a UC Davis researcher, suggesting that increased tobacco control efforts could save more lives than previously estimated.
The researchers linked smoking to more than SEVENTY PERCENT of the cancer deaths in men living in Massachusetts. According to the lead author of the research the study provides support for the growing realization that smoking is a cause of many more cancer deaths than those caused by lung cancer. The full impacts of tobacco smoke, including secondhand smoke, have been overlooked in the rush to examine such potential cancer factors as diet and environmental contaminants. As it turns out, much of the root cause of all cancer deaths was probably smoking all along.
The researchers used National Center for Health Statistics data to compare death rates from lung cancer to death rates from all other cancers among Massachusetts males. The assessment revealed that the two rates changed in tandem year-by-year from 1979 to 2003, with the strongest association among males aged 30-to-74 years.
Smoking is a known cause of most lung cancers, and the study authors concluded that the very close relationship over twenty-five years between lung and other cancer death rates suggests a single cause for both: TOBACCO SMOKE.
The head researcher had this to say about the study. "The fact that lung and non-lung cancer death rates are almost perfectly associated means that smokers and nonsmokers alike should do what they can to avoid tobacco smoke. It also suggests that increased attention should be paid to smoking prevention in health care reforms and health promotion campaigns."
A new analysis linked smoking to more than 70 percent of the cancer death burden among Massachusetts men in 2003. (Credit: iStockphoto)
What’s the bottom line here? If you want to live to see your grandchildren grow up, STOP SMOKING!!!
And now since we’ve had such downer stories, let’s do one that tells us what we can do in our communities to make us all healthier.
EXERCISE FOR YOUR HEATH
What if free exercise classes were offered in public spaces such as parks, beaches and recreation centers? When a city government in Brazil tried such a program, it greatly increased physical activity among community members. A group of health researchers who have studied the program believe it could also work in U.S. cities with warm climates. (And who has warmer climates than the Marianas?)
In Recife, the fifth largest city in Brazil, an initiative was developed and managed by the city that encourages physical activity in 21 public spaces. Physical education instructors teach free calisthenic and dance classes, lead walking groups and provide nutrition information. These activities are offered free of charge each day from 5 – 9 a.m. and from 5 – 9 p.m.
Since 2002, the program, called the Academia de Cidade program (ACP), has enrolled more than 10,000 residents per year and taught 888,000 exercise classes. In the study of the program, researchers found that current and past participants were three times as likely to exercise than residents who had never participated.
The researchers randomly surveyed over 2,000 Recife residents by phone about leisure-time physical activity and walking or biking to destinations. They also observed participation and the level of physical activity at ACP exercise sites. Additionally, researchers evaluated factors related to exposure to one of the exercise sites, such as living near a site, hearing about or seeing the exercise activities and participating in activities. Rates of moderate-to high-level leisure-time physical activity were 19 percent overall, 26 percent among men and 14 percent among women.
Eduardo J. Simoes, M.D., the first author of the paper and director of the CDC’s Prevention Research Centers Program says the project is an effective strategy to stimulate life-long exercise. When exercise is coupled with healthy eating, the physical activity can help prevent and control diabetes, hypertension, and heart disease, resulting in improved quality of life and health.
He also hopes local governments in the United States will someday consider similar programs. "We’ve seen that providing free, accessible exercise and nutrition programs in an urban setting can benefit thousands of people," he says. "We could take related steps to increase exercise and improve Americans’ overall health."
Residents in Recife, Brazil, exercise in the Academia de Cidade program. (Credit: Marcia Munk, Universidade Federal de São Paulo
So . . . Guam legislature and CNMI legislature, are you listening? Mayors, are you listening? Would you like to spend some money to help improve the quality of life for all your citizens? And to you, the reader. Stop drinking the sugared soft drinks, stop smoking and get off your daggan and exercise. Then you probably WILL live to see your grandchildren grow up!
Cruise on over to the Deep Website at www.thedeepradioshow.com to learn more about your health and many other topics. Enjoy!
We talked a little bit last week about some truly strange animals, and I thought this week we’d continue our little sojourn into the animal kingdom. Our first animal is no longer with us, but he was a bizarre little thing.
DINOSAURS COME IN SMALL PACKAGES TOO
We’re all familiar with T-rex and Stegasaurus and Apatosaurus and all the other enormous dinosaurs but big isn’t the only size for dinosaurs. Canadian researchers have recently uncovered a chicken-sized dinosaur that ran on two legs and scoured the forest floor for termites. They are the smallest dinosaurs ever discovered in North America.
They have long, slender legs, stumpy arms with huge claws and jaws like tweezers. One of the paleontologists who discovered them says they look like an animal created by Dr. Seuss.
Scientists named them Albertonykus borealis because they were found in the northern province of Alberta. The small dinosaurs apparently were termite eaters and used their powerful forelimbs to tear into infested logs. Their fossils were dated at 70 million years old.
Albertonykus has relatives in Asia and the recently discovered fossils are evidence of the oldest and most complete dinosaur of its kind known from North America. The researchers say that the skeleton provides evidence that these dinosaurs migrated to Asia through North America.
Migrating chicken-sized dinos, eh? Our next story also examines animal migration but this one has some scary overtones.
CLIMBING THE MOUNTAIN
A study done in Yosemite National Park and recently published in the journal Science has discovered something troubling about the small mammal populations in the park. They’ve done surveys of shrews, mice and ground squirrels and compared their findings with data from 90 years ago and discovered that many of them are headed for higher ground. The apparent reason? Global warming.
The original purpose of the research was not to study climate change, but when they discovered that virtually every studied mammal was found at higher elevations than those reported in the last full scale survey in Yosemite in 1918.
The central Sierra Nevada mountains have seen a general warming, shown not only by a 3 degree Celsius increase in nighttime low temperatures (about 5 degrees F.), but also the receding of glaciers – Lyell Glacier is half the size it was 100 years ago – and the increase in precipitation as rain instead of snow.
While the population movements have not altered biodiversity in the park, UC Berkeley biologists say rapid changes in less than a century could be a problem. Although half the species shifted their ranges, the other half did not, which means communities have been altered and the species interacting with one another have changed.
Although changes in community composition are common, what makes this one different is that it has happened in our lifetimes. It’s the speed of change that has the scientists worried. If the movements are slow, the ecosystem has time to adapt to the changes, but we have no idea of the potential consequences of such rapid change.
The foundation for the current study is a landmark survey of Sierra Nevada birds, mammals, reptiles and amphibians initiated early last century by Joseph Grinnell, founding director of the museum and a zoology professor at UC Berkeley. With a large number of colleagues and students, Grinnell traipsed through the Sierra Nevada – from the Modoc Plateau in the north to the San Jacinto range in the south – collecting specimens and recording for posterity the variety of life then under threat from gold mining and overgrazing.
The current researchers proposed resurveying all the sites visited by Grinnell and his colleagues, starting with the Yosemite transect originally surveyed from 1914 to 1920, which stretched from the San Joaquin Valley through the park and over the Sierra crest to Mono Lake. With funding from the National Science Foundation, the Yosemite Foundation and the National Park Service, the Grinnell Resurvey Project commenced in 2003. This information is the first result of the survey and it appeared on the 100th anniversary of the founding of the museum in 1908.
The researchers found that, of the 28 small mammals observed in the transect, half had expanded their range upward by more than 500 meters, or 1,600 feet. While low-elevation species such as the California vole and the California pocket mouse increased their range by moving upslope, high-elevation species such as the bushy-tailed woodrat and Allen’s chipmunk generally decreased their ranges. Short-lived, fast-breeding species were more likely to expand their ranges than were their long-lived, less fecund relatives.
Upward movement has caused the range of the alpine chipmunk to shrink and possibly put the chipmunk, one of California’s few endemic mammals, at risk of extinction. Although 90 years ago the chipmunk was common on granite slabs in lodgepole pine forests below 7,800 feet, the researchers were unable to find any below 9,600 to 9,800 feet, an upward movement of 2,000 feet.
Similarly, on the eastern slopes of the Sierra, the one-ounce pinyon mouse has moved entirely out of the pinyon pine/juniper belt into a very different habitat, the mountain forest, which is dominated by whitebark pine.
While higher elevation shifts were driven primarily by climate, the researchers noted that lower-elevation changes probably had something to do with land use changes. A third mammal impacted significantly in the past 90 years is the Trowbridge shrew, which used to be the only shrew in Yosemite Valley. Today, with the departure of Indians who regularly burned the valley, the valley is wetter, and the Trowbridge shrew has been totally replaced by the montane shrew, which moved downslope to recolonize the valley.
Animals on the move because of climate change. And yet there are still people who say that global warming is a crock. I hope they can swim!! (or perhaps climb!)
A pika seen at Lembert Dome in Yosemite National Park. (Credit: Emily Rubidge photo)
The pika in the picture is an adorable little fellow, but there are animals out there that are well, Furbies. Do you remember Furbies? They were those adorable little stuffed robots that were all the rage a few years ago. Well, newly discovered primates in Indonesia look like Furbies come to life.
FURBY, WHERE ART THOU?
A team led by a Texas A&M University anthropologist has discovered a group of primates not seen alive in 85 years. The pygmy tarsiers, furry Furby-like creatures about the size of a small mouse and weighing less than two ounces, have not been observed since they were last collected for a museum in 1921. Several scientists believed they were extinct until two Indonesian scientists trapping rats in the highlands of Sulawesi accidentally trapped and killed a pygmy tarsier in 2000.
The researchers trapped three of the nocturnal creatures in Indonesia in late August last year. Pygmy tarsiers have fingers with claws instead of nails, which distinguishes them from nearly all other primates that have nails and not claws. The claws may be an adaptation to the mossy environment in which the tarsiers live.
Over a two-month period, two males and one female were trapped on Mt. Rore Katimbo in Lore Lindu National Park in Central Sulawesi, Indonesia. The scientists used almost 300 mist nets to capture the creatures, then fitted them with radio collars so their movements could be tracked.
The tarsiers live in mountainous terrain at
heights of 7,000 to 8,000 feet. This makes them difficult to get to and their habitat plus the fact that they’re nocturnal has probably saved them from the extinction that everyone believed had overtaken them. The researchers are hoping to convince the Indonesian government to lay on extra protection for these bizarre creatures.
A pygmy tarsier being held by a researcher. The primate weighs less than two ounces and is about the size of a mouse. (Credit: Image courtesy of Texas A&M University)
Chicken-sized dinosaurs, traveling mammals and a living Furby. Welcome to the wonderful world of Earth’s animals! Cruise on over to the Deep Website at www.thedeepradioshow.com to learn more about living Furbies and many other topics. Enjoy!
Jim is, above all, a passionate eco-humanitarian who has developed his own science talk-radio show to inform The DEEP’s listeners about such newsy topics as global warming, shark-finning and reef protection as well as to explore earth’s many underwater and space mysteries.
sailing 12,000 miles and visiting five countries Jim is back here, ready to explore the depths of the ocean to the deepest frontier, space MORE>>
Lady Pam Eastlick is an expert in both the stars
and seas as a graduate of the University of Guam Marine
Lab and the Director of the UOG Planetarium.