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January 26, 2010

Weird Hills on the Surface of Titan

Titan is one of the one of the most exciting places in our solar system. This moon of Saturn has liquid methane playing the role of water on its surface, and water ice playing the role of solid rock. We are just beginning to understand the dynamics at work on this moon, in part because it is shrouded in a thick methane atmosphere. This image was taken on December 28th, 2009 and is giving sicentists new puzzle to solve.

The lines you see in the lower left of the image are rifts similar to features called corona on Venus. On Venus, we think they are caused by heat within the planet that puts stress on the rock. Straight features like this could also be created by surface activity like wind or rainfall.

The star-shaped feature to the right also points to some sort of activity happening in this area. “This star-shaped pattern of the hills indicates something significant happening in the middle of the star,” said Steve Wall of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., a Cassini scientist on the radar team. “It might be caused by tectonic forces, such as the forces that pull the crust of a planet apart, or rainfall that leads to erosion, or an ice intrusion like a dike.”

Scientists don't have any answers yet, but either answer would be exciting. If this was caused by rain, it gives us a better understanding of how liquid methane shapes the surface of Titan. If on the other hand it is caused by some sort of internal heat, it raises all new questions on what the inside of Titan is like. We will just have to wait as Cassini continues to unveil this exciting world.

Image Credit: NASA/JPL

January 20, 2010

Puppies for Evolution

Most of us are familiar primarily with domesticated animals. They are food, pack animals, and pets. Dogs are one of the species that was domesticated relatively early, and now numerous breeds of dog exist, to fit pretty much every taste. Domestication has an interesting interplay with evolution. Far from reducing the pressures on a species, it can create new ones, leading to some pretty profound changes.

Before we can look at that, though, we have to understand how evolution works. Evolution, in its most basic form, is the process by which species change over time. Its driving mechanism is natural selection, or "survival of the fittest." In a given group of individuals, there are going to be differences. Some of these differences help an individual; others give it a disadvantage; most don't do anything at all. A great example of this is the peppered moth of England. Some individuals were a light color, matching the bark on the lichen trees where the moths live. Others were a sooty gray. Before the Industrial Revolution, the dark moths were pretty rare; birds could see and eat them pretty easily. During and afterwards, however, the soot on the trees gave the dark moths the advantage, and the light moths became rare. Now, as the pollution levels have fallen, the light moths are making a comeback. It's the classic example of natural selection in action.

Now, I'm sure by this point you're trying to figure out why I started with puppies when I was just going to talk about moths. I'm getting back to puppies now. A new study suggests that selection is well at work in domestic dogs, to an extent that doesn't occur in nature. This is artificial selection, rather than natural selection. See, domestic dogs don't face the same pressures as their cousins, wolves and coyotes. They don't have to chase down live prey and eat tough, raw meat. There is no shortage of easily accessible food, water, and shelter. Therefore, domestic dogs aren't playing the game of "survival of the fittest;" rather, they are playing "survival of the cutest." The study specifically looked at skull shapes of various carnivores, including several breeds of domestic dog. The results are impressive: it turns out a cat and a walrus have more in common, head-shape wise, than a collie does with a Pekingese. Because people are the main pressure selecting for characteristics, rather than practicality, a breed like a pug can survive as a pet. In the wild, a pug would be unable to breathe, eat, or avoid anything that wanted to eat it. Cute? Maybe. Practical? No.

The pressures on dogs, and other domestic organisms, are an interesting study in evolution. Freed from the very limiting pressures of natural selection, these creatures can develop characteristics that would be totally impractical in the wild. From this diversity, humans pick the characteristics they like best, and breed those specifically, while other characteristics are deemed ugly, and are selected against. The process is fast, and easy to observe. This artificial selection is a proof-of-concept experiment for natural selection and the Darwinian model of evolution.

Source: Science Daily- "'Survival of the Cutest' Proves Darwin Right"
Charles Darwin's On the Origin of Species: A Graphic Adaptation, Michael Keller (Amazon)

January 19, 2010

Scientific Unknowns: The Mind-Brain Dualism

Of the many interesting questions presented by psychology, the idea of the brain vs. the mind has some of the greatest impacts. The idea's been around for a long time: both Sigmund Freud and Emil Kraepelin proposed a difference between the mind and the brain, along with ways to study it. Even before that, Greek philosophers pointed out the problem of the relationship between the mind and the body.

The dualism basically states that, while the brain and the mind are clearly connected, the two are separate entities. The brain is easy to define. It is the physical bundle of neurons inside a person's head. It is capable of sending chemical signals to the rest of the body, allowing for movement and other functions. Even the simplest animals have some sort of brain. The mind, however, is not as easily explained. It is usually conceptualized as the consciousness, the "I" of a person. It is not something present, as far as we know, in any other species. There appears to be a connection between the two: for instance, if a person sustains brain damage from a disease or an injury, their mind also changes. They may have a different personality, lose memory, experience different emotions. But, research has not yet show exactly how the two are connected.

The impacts of this question are huge, however. It is a scientific, religious, philosophical, and practical question. It leads to questions such as these: If the mind/consciousness/soul is separate from the physical brain, then can it persist after death? If it is not separate, then is there even such a thing as a soul? Among the scientific community, there isn't really a consensus. According to a study by the University of Edinburgh and the University of Liege, over 1/3 of medical professionals regarded the mind and brain as separate entities. Despite this, however, in the same study a majority thought the mind and brain were not separable. Thus, there are really only questions at this point, rather than answers.

As David Tresan puts it, "In light of the prevailing scientific bias toward reductionism, how then are we to think about the relationship between mind and brain without on one hand simply reducing the former to the latter or without on the other invoking dualism and thereby abandoning altogether the quest for any such relationship?" In other words, how can we think about the mind and the brain as separate, yet connected? Only further advances in neuroscience and psychology will tell.

Sources: Mind-Body Problem: New Approaches
Articles below found through PubMed
"150 years of Freud-Kraepelin Dualism", Katharina Trede
"Dualism Persists in the Science of Mind", Athena Demertzi et al.
"Jungian metaphychology and neurobiological theory", David I. Tresan (full article found through EBSCO)

January 18, 2010

3 Ways You Can Support Science and Reason (for Free)

I have been passionate about science for many years now. Stemming from this passion is my desire to be involved in active science, and spread the amazing world science reveals. While donations can always be used help to spread good critical thinking, there are many things you can do even if you are strapped for cash.

1. Talk about it

It may not seem like much, but one of the best things you can do is just to share your passion with friends and family. If you see a science story that catches your eye, tell people about it. People are generally interested in science to varying degrees, so share what you know. The more people are talking about science, the more it will be a part of the public conciseness.

2. Join a Citizen Science Project

There are lots of projects out there where all the scientists need is a little of your time and help. A perfect example of this is the Galaxy Zoo project which I have mentioned several times before. Because of their success they have now expanded into Zooniverse. This includes 4 research projects you can help with watching everything form supernova to our own sun. You could also help with the mystery of the star Epsilon Aurigae with Citizen Sky. These are just a few examples from my own field of interest, but you can find projects across many other disciplines with just a little looking.

3. Volunteer at a Local Science Museum

This is a really fun way to spread excitement about science. There is nothing better than showing a child a simple demonstration and having their eyes light up. This is also a great way to meet other people who share your interest. As you teach people about science, you will probably find your own knowledge of science growing. Teaching any subject is a great way to solidify, and expand, on your own understanding.

These are by no means the true end to the list, but I want to keep it short for now. Maybe I will expand on this list in the future. In the meantime, feel welcome to put anything you have done to support science in the comments below.

January 14, 2010

Direct Spectrum of an Exoplanet taken for the First Time

Analyzing the spectrum of light coming from a star or planet gives us a huge insight into the composition and environment of that object. If we ever find a exoplanet we think could harbor life, one of the first things we will want to do is get a light spectrum. The would potentially allow us to find free oxygen (a distinct signature of life) in its atmosphere. This makes developing the technique of attaining exoplanet spectrum a huge necessity.

The breakthrough was done on a gas giant orbiting the star HR 8799, which is just slightly larger than our own sun. What makes this measurement special is not that we got a spectrum, but that we got a spectrum straight from the planet itself. In the past we have analyzed the light from a star, that passed through the atmosphere of its exoplanet. While this is still a valid technique, it is only possible to do with planets that have the right orientation to our own solar system. Because only a small fraction of planets have such an orientation, this opens the door to studying the growing number of exoplanets. This planet is extremely hot at about 1,800 degrees Fahrenheit, causing it to pouring out infrared light. This made it a great target for trying this technique, but it was still no walk in the park. “It's like trying to see what a candle is made of, by observing it next to a blinding 300 Watt lamp – from a distance of 2 kilometres [1.3 miles],” said Markus Janson of the University of Toronto, lead author of the paper.

As is almost to be expected with the first results from any new technique, the results from this spectrum were totally unexpected. This planet's spectrum didn't match any of the models we had for gas giants. The current thinking is that this planet was one the verge of becoming a brown dwarf star. With roughly 10 times the mass of Jupiter, it is probably still emitting heat from when it was formed. The composition is also not what was expected from previous models. This once again show how young our models of solar system formation really are.

As we continue to do this on more planets and refine the process, I'm sure we will continue to find things that surprise us. I still think the most exciting part of all this is the ability to use this to find other life in the universe. We will have to wait and see what the future holds, but I think it is promising.

For More Information see the European Southern Observatory site
Image Credit: ESO/M. Janson

Dynamic Earth: Haiti

I'm sure most of you have heard about the massive earthquake in Haiti by this point. It was a devastating quake. The first shock was a magnitude 7.0, out of a scale of 10. It has been followed by numerous aftershocks, ranging from 4.0 to nearly 6.0. In the face of such a distaster, it's easy to ask why the earthquake occurred. I've seen three such explanations. The first two of these are completely ridiculous.

The first is a rather bizarre idea this was not a natural earthquake, but rather a weather weapon aimed at Cuba that missed. It claims that the fact that there was a little earthquake in California (presumably a test of the weapon?) followed by a huge earthquake in Haiti is too suspicious, and not coincidence. (source: NowPublic News)

The second is given by Reverend Pat Robertson. He believe that this earthquake was punishment, for Haiti's pact with the devil.
“They were under the heel of the French, uh, you know Napoleon the 3rd and whatever, and they got together and swore a pact to the Devil. They said, 'We will serve you if you'll get us free from the French. True story. And so the Devil said, 'Okay, it's a deal.’ And, uh, they kicked the French out, you know, with Haitians revolted and got themselves free. But ever since they have been cursed by, by one thing after another, desperately poor. That island of Hispaniola is one island. It’s cut down the middle. On the one side is Haiti on the other side is the Dominican Republican. Dominican Republic is, is prosperous, healthy, full of resorts, etcetera. Haiti is in desperate poverty. Same island." (Source: ABC News)

Both of these explanations are uninformed, poorly articulated, and make the Haitian earthquake someone's fault. In fact, the Haitian earthquake was caused by a slip-strike fault, between the North American and Caribbean plates. These two plates slide along each other at a rate of 7 mm per year. Tension has been building up in the fault, and it finally snapped on Tuesday. Along with being a strong quake at magnitude 7, it's source was only about 6 miles down. This means that the crust could not absorb and diffuse the shock. The ground shook at Port-au-Prince for as much as a minute, which is very long for an earthquake. The fact that there is so much devastation, therefore, isn't a surprise. (source: USGS)

Right now, the people of Haiti don't need condemnation or conspiracy theories. There is no evidence whatsoever for a working weather missile even existing. Plus, earthquakes aren't weather; they're a geologic force. And, earthquakes happen frequently in California: the whole state is caught on the boundary between two of the largest pieces of the puzzle. Any supposed pact with Satan occurred in 1803. The people there today are not being punished for something 200 years ago. Condemning them, saying this is their own fault, is not going to help their condition at all.

Haiti is the poorest country in the Western Hemisphere; at least 80% of their population is below the poverty line. Disease is a major problem, and will only get worse with the destruction. Children there were literally living off of mud pies; now, food will be even harder to come by. (source: CIA World Factbook) And, while the earthquake itself killed over 100,000 people, many more will die if they don't get help. We live on an indifferent planet. It is neither benevolent or malicious. These natural events will occur whether people are  there or not. But when it does hit a populated area like Haiti, we, as a species capable of supporting one another, can help. Please donate to one of the organizations below, if you haven't done so already.

Support Doctors Without Borders in Haiti

More on earthquakes and plate tectonics.

January 13, 2010

Sea Slug Going Green

It's pretty common knowledge that plants use chlorophyll to turn sunlight into energy. It's what gives them their green color. Animals typically don't have chlorophyll, and so need to consume plants or other animals to gain the energy necessary to survive. (A few single cell plankton produce chlorophyll, but they barely meet the definition of an animal) A newly discovered sea slug has learned how to cut out the middleman. According to Sidney Pierce, the biologist who discovered these creatures, they can steal the chloroplasts from algae, as well as the genetic material needed to make chlorophyll.

This is possibly one of the coolest discoveries I've seen in marine biology, along with the tool-using octopus. Scientists knew that organisms could swap genetic material; bacteria do it all the time. However, the fact that this sea slug can steal the genes to make chlorophyll so successfully is remarkable. Baby sea slugs are born with the ability to produce chlorophyll, although not the ability to produce chloroplast that allow them to use the chlorophyll. It's a very neat evolutionary adaptation. The sea slugs have integrated one of the traits that make plants so successful. How, scientists have no idea. There is no known mechanism that lets the DNA transfer like this. It's another area to be further researched.

Source: Live Science- Surprising Sea Slug is Half-Plant, Half-Animal

January 12, 2010

Coming Out of the Water

Earth, 400 million years ago. It's not the sparkling gem of blue and green we see from space today. The oceans are still there, but the continents are mostly barren: plants emerged from the oceans only 30 million years ago. They are still concentrated along the coasts and in wet areas. Taking a closer look, we find a few arthropods have crept out of the water too. Sea scorpions pick up dead fish along the coasts, and a few insects buzz among the ferns. Most life is still in the water, though. This is the Devonian period, and something's about to change. 380 million years ago, the first vertebrates, amphibians, came out of the water. Fossils like Tiktaalik show the transition between the fins of fish and the feet of land vertebrates. They are some of the most incredible fossils, and provide a lot of information about the track life took on the early Earth.

A new fossil discovery adds a new twist to this story of life. A new -actually, a very, very old- set of fossil footprints has been discovered. They are obviously those of a vertebrate, rather than an arthropod. Just the fossil itself is exciting, but the twist is that it is 18 million years older than Tiktaalik and similar tetrapods. Even in geologic time, that's significant. That means that amphibians evolved, not in the middle of the Devonian around 380 million years ago, but 395 million years ago at the beginning of the Devonian. Also, these footprints aren't small; researchers estimate that the creature that made them was up to 3 meters (nearly 10 feet) in length. Thus, tetrapods and their predecessors, like Tiktaalik, had evolved much earlier than originally thought. Also, it means that the intermediate creatures were more successful than scientists had previously thought.

This discovery is exciting because it fundamentally changes the beginnings of land vertebrate, which later led to most of the animals we are familiar with today. I expect that this discovery will be followed up by not only more footprints, but by skeletal evidence as well. After all, we know what to look for now. As was the case with Tiktaalik, the fossil record suggested that there should be a specific type of creature between fish and amphibians in a pretty small range of rocks. Paleontologists looked there, and found it. This enlightening discovery will probably be followed up in a similar manner. It's an exciting example of how science is always changing.

Source: Science Daily- Fossil Footprints Give Land Vertebrates a Much Longer History

January 11, 2010

SETI vs. UFOlogy: A Look at the Nature of Science

Are we alone in the universe? It is a great question and one that I think everyone is interested in. As with many big questions, there are different ways of approaching it. This makes it a wonderful topic for looking at the differences between science and pseudoscience.

SETI, the Search for ExtraTerrestrial Intelligence, is a private group who is trying to scientifically find evidence of other life in the universe. They use radio telescopes to look for signals that might be sent from extraterrestrials. When SETI detects a signal they think could be from some sort of alien intelligence, they first try to falsify their results. They check if it could have been caused by some radio emitter on the earth, or some known astronomical object. They have other scientists check their results by looking to see if they find the same signal. In their own FAQ, SETI explains this perfectly.
In the past, there were several unexplained and intriguing signals detected in SETI experiments. Perhaps the most famous of these was the "Wow" signal picked up at the Ohio State Radio Observatory in 1977. However, none of these signals was ever detected again, and for scientists that's not good enough to claim success and boogie off to Stockholm to collect a Nobel Prize. You wouldn't believe cold fusion unless researchers other than the discoverers could duplicate it in their labs. The same is true of extraterrestrial signals: they are credible only when they can be found more than once.
 The other side of the coin is the UFOlogists. While some sites try to be scientific, they miss some key components. First, the whole premise of their argument is flawed. They are taking photos and anecdotal reports of unknown objects, and using those as evidence. I wrote just recently why this doesn't work. Briefly, if you have an unknown it is simply that, an unknown, not evidence. UFOlogists also will ignore alternative explanations that contradict their interpretation of the evidence. For example, they will ignore the idea that a video or photo could have been faked. Instead, they make unsupported statements like, "They can't all be fakes." There is also the tendency to portray scientists as "dogmatic." To anyone who works in science or with scientists, this claim is ridiculous. Scientists love new ideas that challenge what we think is true. Those ideas, however, must meet the standard of evidence.

In his Cosmos series, Carl Sagan made a great point in regard to UFOs. He said, "What counts is not what sounds plausible, not what we'd like to believe, not what one or two witnesses claim, but only what is supported by hard evidence, rigorously and skeptically examined." We all want there to be a easy cure for all illness, but that doesn't make it real.

When you encounter a claim ask which model the claimant is following. Many cases are not going to be straightforward, but their are some clues you can look our for. Is the claimant putting their evidence out to scientists to examine, or makes excuses as to why scientists don't support them. Do they try and prove their own claim wrong, or do they ignore the arguments made against them. I hope that one day (preferably within my lifetime) we find life somewhere beyond our little planet. This is a proposition that excites all of us. It is interesting how people can take such different approaches to solving the same problem. Science is the tried and tested method for exploring the world, whether or not it gives us the answer we want.


January 5, 2010

Kepler Finds Weird New Exoplanets

The Kepler Space Telescope is a attempt to find potentially habitable worlds around other stars. Those discoveries are still probably a little ways off, but Kepler has found its first 5 planets. These findings were anounced on Monday, and provide new mysteries for scientists to solve.

The planets Kepler found are called "hot Jupiters". This is because they are approximately the same size as Jupiter in our own solar system, but very close to their parent stars. “We expected Jupiter-size planets in short orbits to be the first planets Kepler could detect,” said Jon Morse, director of the Astrophysics Division at NASA. “It’s only a matter of time before more Kepler observations lead to smaller planets with longer period orbits, coming closer and closer to the discovery of the first Earth analog.” Hot is actually a bit of a understatement in this case since they are well over 2000 degrees Fahrenheit. Still, these 5 are the first to be confirmed planets out of over 100 candidates that have been found. Most of the over 400 exo-planets we have found to date are hot Jupiters, but Kepler's new planets have some unique oddities.

Saturn is the least dense body in our solar system and would float in water (assuming you can find a big enough lake). One of the new planets discovered by Kepler puts Saturn to shame, having a density close to styrofoam. This makes it the least dense planet ever found and poses the mystery of how it formed. Other objects found appear to be planet like objects, only they are hotter than the stars they are orbiting. Ground based observations are looking into these objects and I am curious what they will conclude.

Right now the Kepler planet count is at 5, but this is just the start. These results push the limits of what kinds of planets exist in the universe, and that is exciting. I think this is just a taste of what is to come.

Universe Today

Image Credit: NASA