Skepticism and Daily Health: CAM Overview

Each day, I notice a lot of advertisements for various "medical" and "health" products. Organic produce is commonly sold in grocery stores. Chiropractic clinics and herbal suppliments are often advertised on television. I've even seen and heard ads for psychic healings and religious exorcisms. All of these products and services fall under the heading of "CAM", or complementary and alternative medicine.

I knew that these sort of treatments were popular. I had no idea exactly how popular. According to WebMD and a study by the Center for Disease Control's National Center for Health Statistics, Americans spend 11% of their health care budget on alternative medicine. This totals to around $34 billion. It's a lot of money going toward... what, exactly?

This is how Mayo Clinic defines it.

Complementary medicine is thought of as treatments used in addition to the conventional therapies your doctor may prescribe, such as using tai chi or massage in addition to prescription medicine for anxiety.
Alternative medicine is generally thought of as being used instead of conventional methods. For example, this might mean seeing a homeopath or naturopath instead of your regular doctor.

Types of alternative medicine include acupuncture, homeopathy, chiropractic, herbal suppliments, and energy therapy, among others. The reason they are alternative forms of medicine is because there have been no conclusive studies to show they work. From Mayo Clinic again:

Conventional doctors have good reason to be skeptical when it comes to complementary and alternative medicine. Some complementary and alternative medicine practitioners make exaggerated claims about curing diseases, and some ask you to forgo treatment from your conventional doctor to use their unproven therapies. Some forms of complementary and alternative medicine can even hurt you.

Conventional medicine relies on methods proved to be safe and effective with carefully designed trials and research. But many complementary and alternative treatments lack solid research on which to base sound decisions. The dangers and possible benefits of many complementary and alternative treatments remain unproved.

Medicine is one of the scientific fields most abused by advertising scams and false claims. Still, not all alternative medicine is bad. I personally went to a chiropractor for years... to realign my back, not to treat some other disorder. When looking into things like CAM services, be sure to check out the science behind them, so you know exactly what you're paying for.

Credit: WebMD- Americans Spend $34 Billion of Alternative Medicine
Mayo Clinic- Complementary and Alternative Medicine: What is it?

What is Science? (The Unfalsifiable Hypothesis)

I mentioned in my post about the scientific method that a hypothesis must make predictions. The reason for this is that to test that hypothesis, you see if the predictions hold true. A hypothesis that makes no predictions is unfalsifiable.
Here's the problem. If a idea is unfalsifiable,it is a dead end. The classic example of this is Carl Sagan's dragon. Some one claims that they have a dragon in their garage. Steve Novella from the Skeptic's Guide to the Universe described this famous example on Neurologica.

"Sagan also used his dragon analogy to illustrate the logical fallacy known as special pleading – inventing a unique and special reason to explain why each type of evidence that could potentially validate a claim is lacking. There is no reason to speculate ahead of time that the phenomenon in question should have such features, they are just invented ad hoc to explain away the lack of evidence. For example: question: 'Can I see the dragon?' answer: 'No, it’s invisible.' Question: 'Can I feel it?' Answer: 'No, it is non-corporeal.' 'Can I measure the heat of its fiery breath?' 'No, it breathes heatless fire.' Etc."

If it can't be falsified, it's just not science. Science works by using evidence to evaluate ideas. If you create a claim that is immune to evidence, it simply is not science.

As a note, it is technically possible for an unfalsifiable claim to be true. It would be extremely unlikely however. Do you think I have a invisible, non-corporeal dragon in my garage?

Prehistoric Proteins

For a long time, I considered the idea of collecting DNA or proteins from fossils to be all Hollywood. I've never seen Jurassic Park, but the premise just sounds wrong. Collecting dinosaur DNA from 100 million year old blood in the body of a mosquito preserved in amber? Highly unlikely.

However, a couple of new discoveries have popped up lately that make the idea of collecting molecular fossils less science fiction. The first of these dealt with finding the color of an extinct type of bird.

The Moa was a giant flightless bird, rather like an emu. They lived on New Zealand up until humans arrived near the 13th century AD, and are now extinct. There were no records of how these birds were colored. Reconstructions were made based on the moa's living relatives, emus and kiwi birds, but they were just educated guesses, rather than solid data.

Nicholas Rawlence, of the University of Adelaide, has developed a new technique that answers the question of the moa's coloration. They can extract mitochondrial DNA from fossilized feather shafts, and use that information to determine exactly what color the feathers were: in the case of the moa, brown with white tips. This technique can be applied to the remains of other extinct bird fossils found on New Zealand, answering other questions of how many species there were, and how factors like climate affected them.

Still, moa fossils are not nearly as old as dinosaur fossils (a few hundred thousand years, vs. 10s to 100s of millions of year). A second story I found is more intriguing, because they did find traces of genetic material... in a T-Rex.

The T-Rex in question was a very well preserved specimen from 68 million years ago. The initial analysis done on it found traces of collagen in the fossil bone. This finding was controversial, and many attributed the finding to contamination or statistical error. A new study, however, returned the same results: peptides of collagen do exist in the bone. It's an exciting new discovery, and might help, with more data, to determine how dinosaurs are related to each other, and to their living descendants: birds.

The odds of ever getting a full strand of DNA from a dinosaur fossil is extremely low. They are simply too fragile to last for 100 million years. Jurassic Park will stay a fictional idea. However, as these two findings show, there is some potential in finding bits of genetic material in the fossils, which may help clear up questions on coloration, speciation, extinction, and more.

Credit: Discovery Channel- Feathers Revealing Extinct Moa's True Colors
Science Daily- Reexamination of T-Rex Verifies Disputed Biochemical Remains

Do you want to get involved in Real Science?

If so, this is your opportunity. A group called Citizen Sky is looking for volunteers to help them study a very interesting and bizarre star system. Regardless of where you live or your background knowledge, they want your help.

Just for a little background: Citizen Sky is studying a star called Epsilon Aurigae. Don't be scared off by the name, because this is a really interesting star system. Just as planets orbit a star, stars can also orbit stars. These are called binary star systems. When one of the stars passes in front of the other, we get an eclipse. When this happens, we see the brightness of the total star system dim. In the case of Epsilon Aurigae we see an eclipse about once 27 years. The really weird thing is that when scientists looked at the spectrum they could only see the light from one star. Since this was discovered, the question has been what is eclipsing this star.

This is where Citizen Sky needs your help. The next eclipse is predicted to start this August. They are looking for people to help them with everything from making the observations (which you don't need any special equipment for) to studying the data and doing outreach. Citizen Sky will give you all of the skills you need to help them out, so no background knowledge or experience is necessary. Projects like this is a great way to really understand the process, and sheer joy of science.

For more information I recommend the July 7 episode of the 365 Days of Astronomy
To get involved go to www.citizensky.org

Driving Blind

When learning to drive, I fought the idea as much as I could. I was scared of the idea of driving, and really didn't want to get behind the wheel. It didn't help that everyone I talked to immediately launched into stories of various accidents and close calls they've had while driving. After reading this story, however, I realized that my issues with earning a driver's license were nothing compared to some peoples'. After all, how can you drive if you're blind?

A new technology from the Virginia Tech School of Engineering may open up the possibility of driving to those that can't see. Using laser sights, a voice command interface, a vibrating guide vest,and other innovative technology, a retrofitted dune buggy can give a blind individual precise instructions to drive. As the Mythbusters proved, it is possible for a passenger to give good enough instructions to help someone blind drive without crashing. However, these instructions can be too vague. For instance, "Turn left." Does that mean turn left sharply, right now, or to turn left gradually in 10 feet? The technology in the dune buggy is precise enough to always give detailed driving instructions. This is a first step to not only letting the visually impaired drive, but also to other technologies to improve their options in day-to-day life.

Credit: Science Daily- Blind Can Take Wheel With Newly Designed Vehicle

See the Mythbusters do it at Discovery Channel

Scientific Unknowns: Dark Matter (Yes, it Really Exists)

When I teach astronomy, one of the most common questions I hear is "Is dark matter real?" In order to answer this question let me give an example.

Let's say that you are riding your bike and suddenly you start to hear a grinding sound. You start to slow down and the sound goes away. Let's call this Dark Sound. What you could do is try to describe the sound. If you have a speedometer on your bike, you may be able to say that it only happens when you are going faster than 10 miles per hour. You might try changing gears and find that it only happens when you are on your second rear gear. By doing this you can describe the problem, but you may still not know what the problem is. Dark Sound is a place holder name until you take it to a mechanic and they can tell you what's wrong.

Dark matter (and dark energy which I will talk about later) is a place holder name. The problem is with galaxies. When we look at a galaxy we can estimate how much stuff there is in that galaxy. We can then figure out how much gravity that stuff should have. The problem is that there is five times more matter in galaxies than we can see. It is estimated that over 90% of the matter in the universe is dark matter.   Scientists are getting closer and closer to understanding what this dark stuff is, but the answer still isn't there. We have imaged the effects of dark matter on small galaxies, and now understand there to be halos of dark matter around large galaxies. Right now, many of the world's leading astronomers and cosmologists are trying to figure out what this dark stuff is; when they do I'm sure that the answer will change how we see the universe.

For more I recommend Astronomy Cast

Citizens help scientists find "Green Pea" Galaxies

Many people think of science of something reserved for the researchers who have earned their PhD and spent years in a lab. 200 years ago this would have been about right, but things have changed. In reality, science is a community of people working together. More and more now researchers are asking for the public to help them. The universe is a big place (really big). Scientists often have more data they they can process by themselves. This is why a group of researchers started a website called Galaxy Zoo.

If you haven't tried Galaxy Zoo I highly recommend it. They have taken images of galaxies from the Sloan Digital Sky Survey and have asked volunteers to classify them. By doing this they have been able to make some discoveries that may have escaped them otherwise.

Most galaxies come in two breeds, spiral and elliptical (pictured above). The Galaxy Zoo team discovered a new class of galaxies that are being called green peas (below). “These are among the most extremely active star-forming galaxies we’ve ever found,” said Carolin Cardamone, an astronomy graduate student at Yale and lead author of the paper, to be published in an upcoming issue of the Monthly Notices of the Royal Astronomical Society. This is simply amazing because these galaxies are 100 times less massive than our own Milky Way, and forming stars 10 times faster.

I think the credit for this discovery really belongs to all of the people who help the Galaxy Zoo team with their work. 10 of the volunteers are even mentioned in the paper for their contribution. “No one person could have done this on their own,” Cardamone said. “Even if we had managed to look through 10,000 of these images, we would have only come across a few Green Peas and wouldn’t have recognized them as a unique class of galaxies.”

All images are courtesy Sloan Digital Sky Survey
The Yale press release can be found here

An Invisibility Cloak for Earthquakes

Earthquakes are among the most feared natural disasters. They reshape the landscape and wreck cities in their path. Major earthquakes can cause tsunamis (aka tidal waves), fires, landslides, floods, and a whole array of additional problems. However, a new technology may be able to buffer against earthquakes, protecting cities and towns, at least.

The idea is actually pretty simple. Set a series of large, plastic rings around an area you want to protect. Be able to change how stiff these rings are. Then, when an earthquake occurs, change the stiffness of the rings to transfer the energy somewhere else. The reason this would work is because earthquakes are really waves of energy moving through the ground. The "cloak" created by the plastic rings would nuetralize the waves directed at the city, diverting them elsewhere. Thus, the area around the "cloak" would still be affected. However, anything within the "cloak" would sustain little or no impact from the earthquake.

This technology is still in an experimentation stage. It works in small-scale models in the lab well, so real-life trials are underway. It doesn't elimate damage or risk from earthquakes, however. It is simply a way to help protect areas that are at a lot of risk from major earthquakes. Hopefully, this technology will become a way to reduce major disasters like the earthquake in China last year.

Credit: Science Daily- 'Invisibility Cloak' Could Protect Against Earthquakes

Images from the Eclipse of the Century

One of my life goals is to see a total solar eclipse. Every time one happens, I love looking at the amazing images that come out.

A total solar eclipse occurs when the Moon passes between the Sun and the Earth. If you are standing in the path of the Moon's shadow, you see the light from the sun blocked. At totality (image above), the entire disk of the Sun is blocked by the Moon and you can see the solar corona.

On July 22nd there was a total solar eclipse. The eclipse could have been seen from many places in eastern Asia including India and China. This eclipse is being called the "eclipse of the century." The reason is that the sun was eclipsed for more than six minutes. This is the longest totality of any eclipse this century. NASA even saw a partial eclipse with the Hinode satellite (above). This is taken in the x-ray part of the light spectrum.

If you want to see more images you can find some on the Discovery Channel website or at NASA.

Images Courtesy NASA/JAXA

Lightning, Life, Cosmic Rays, and Climate

Of all weather phenomena, lightning is one of my favorites. It's amazing that electricity can build up in the air, then release in a sudden burst of light and sound. It can ignite forests, and melt dirt or sand into a clump, called a fulgurite. Lightning is terrifyingly powerful, and really neat to watch.

I recently ran across a couple of articles about lightning. The first discusses new findings in the way life developed. Many bacteria have a gene that allows them use phosphite, a rare compound created almost exclusively by lightning strikes. When life first developed, around 4 billion years ago, however, phosphite was more common. It was introduced by meteorites, as well as lightning, and was more easily avaliable than the common phosphate. Today, phosphite is so rare that it is no longer metabolized. But many bacteria, like E. coli, still have the vestigial ability to use it.

The other article discussed how cosmic rays could influence lightning, and how that, in turn, could influence the climate. Researchers in Portugal suggest that the occurance of lightning is related to the solar cycle. When there is a lot of solar activity, there are fewer charged particles in the Earth's atmosphere, causing more lightning. When the Sun is quiet, there is more cosmic ray flux, more charged particles in the air, and so fewer lightning storms.
This relates to climate change in an unusual way. Because of how the greenhouse effect works, the amount of cloud cover affects global temperature, as well as the amount of greenhouse gases. Thus, when solar activity is up, there is more cloud cover and more lightning along with it. This increase would about cancel out the effect of greenhouse gases during that short period of time.

The impacts of lightning are varied, and can be quite significant. And the occurence of lightning itself is amazing. There is nothing quite like seeing a lightning strike. It is terrifying, but also mesmerizing. It's one of the most interesting forces in nature.

Credit: Discovery News- Lightning-Baked Soils Helped Spark Early Life

Science Daily- Could Cosmic Rays Influence Climate by Charging Up More Frequent Lightning Storms?

Digging Dinosaurs

Paleontologists have found all sorts of trace fossils from dinosaurs: footprints, nests, coprolites, stomach stones, and more. Paleontologist Anthony Martin, of Emory University, has recently added a new type of trace fossil to the list: dinosaur burrows.

Martin has found two seperate dinosaur burrow fossils thus far. The first, in Montana, contained the fossils of a small adult and two babies. Then, about a year later, he found a series of very similar burrows in Victoria, Australia.

There are a few different theories proposed to explain these burrows. One is that they were nest sites. The Montanan fossil supports this well. The other theory is more interesting. Burrowing can help insulate animals from extreme conditions. This would especially make sense with the Australian burrows. At the time they were formed (around 110 million years ago), Australia had just seperated from Antarctica, and was near the South Pole. Dinosaurs living there would have faced cold temperatures and long periods of darkness. Burrowing, along with sheltering in forests and hollows, might have helped these creatures survive.

The idea of a burrowing dinosaur is fascinating. Dinosaurs have been found to fit most other niches: giant grazers, leaf-eating browsers, smaller forest carnivores, and almost any other environment you can imagine. These new, burrowing dinosaurs fill in another niche, that scientists had previously thought was only held by the small mammals and reptiles of the time. It's an exciting new possibility. And, now that paleontologists know what to look for, I expect a lot of new dinosaur burrows will pop up over the next couple of years.

Credit: Science Daily- Down Under Dinosaur Burrow Discovery Provides Climate Change Clues

A Portrait of Life and Death in the Universe

This is an amazing photo. You are seeing the galaxy NGC 1097. At the center is a massive black hole weighing in at about 100 million times the mass of our sun. Our own Milky Way galaxy has a black hole at its center as well; however, it weighs in at only 4 million times the mass of the sun. The bright center of this image is likely to be gas and dust swirling around the black hole on its way to its demise.

This image was taken in the infrared by the Spitzer Space Telescope. The ring around the black hole is a area of intense star birth. The high amount of star formation may be due to all of the material that is flowing towards the galactic center.

Infrared telescopes need to be kept cold to take the incredible photos we have come to expect from telescopes like Spitzer. Unfortunately, Spitzer has run out of liquid helium coolant. Spitzer is slowing warming up and in the next week will start it's "warm mission." I suppose "warm" is relative since it's new temperature will be -406 degrees Fahrenheit. Spitzer has been operating at -456 degrees Fahrenheit (only about 3 degrees above absolute zero) for the last few years. Spitzer is definitely one of my favorite space telescopes because it has produced so many great images like this one. The universe can be very photogenic with the right telescope.

Image Courtesy NASA/JPL-Caltech

Enceladus's Ocean Debate

Last month I wrote about how scientists were in a heated debate on whether or not Saturn's moon Enceladus has a sub-surface ocean. This is cutting-edge science. We have both sides trying to get more evidence and figure out what's going on with this weird moon. Yesterday, NASA released a new piece of evidence that may tip the scales.

A team from the Southwest Research Institute in Texas, used the spectrometer on Cassini to find ammonia in the plumes that are shooting out of Enceladus's surface. The interesting thing about ammonia is that it is an antifreeze. According to the NASA report ammonia can allow the water to remain a liquid at temperatures as low as -143 degrees Fahrenheit. Hunter Waite, the Cassini Ion and Neutral Mass Spectrometer Lead Scientist from the Southwest Research Institute in San Antonio said "Given that temperatures in excess of 180 Kelvin (-136 degrees Fahrenheit) have been measured near the fractures on Enceladus where the jets emanate, we think we have an excellent argument for a liquid water interior."

This is a really interesting result and has powerful implications. I predict, however, that this will not end the debate. We really need some piece of definitive evidence. I hope that there is a liquid ocean because that opens up the question of whether or not there is life on Enceladus. The moons of the outer planets are exciting places that I am sure have many more surprises in store. I can't wait to see what they are.

Source- NASA

Scientific Unknowns: Mars' Methane Leak

In January of this year, researchers using two telescopes at Mauna Kea in Hawaii found large amounts of methane in Mar's atmosphere. Their findings showed that the methane varied on location and time of year. For scientists, this discovery is really exciting. "Methane is quickly destroyed in the Martian atmosphere in a variety of ways, so our discovery of substantial plumes of methane in the northern hemisphere of Mars in 2003 indicates some ongoing process is releasing the gas," said Dr. Michael Mumma of NASA's Goddard Space Flight Center in Greenbelt, Md. "At northern mid-summer, methane is released at a rate comparable to that of the massive hydrocarbon seep at Coal Oil Point in Santa Barbara, Calif."

Since methane doesn't just hang out in Mars' atmosphere, where is it coming from? So far there are two main ideas. The first is that there is some geologic process under the surface that is producing methane. If this is true, then Mars is not as geologically dead as we thought. The other possibility got a lot more press when the story was released. This is the idea that microbial life under the surface is expelling this methane as part of its metabolism.

As exciting as the possibility of life on Mars is, we can't jump to conclusions. The reality is that we know the methane is there, not what is producing it. Regardless of what the answer is, it will be extremely exciting for planetary scientists.

For a more in depth look I recommend Phil Plait's review at Bad Astronomy

Image Credit -NASA

The Answer is in: Jupiter was hit!

Two days ago I mentioned that a amateur astronomer saw a new dark spot on Jupiter that was suspected to be an impact. Yesterday, scientists at the Keck observatory in Hawaii confirmed that this new feature is in fact a impact, and not a storm. This is only the second time astronomers have seen an impact on another planet. The first time was when Shoemaker-Levy 9 hit Jupiter in 1994.

The scientists were looking in the infrared and saw the "scar" from the impact. Leigh Fletcher, a NASA postdoctoral fellow at JPL who helped in getting these latest observations said, "Given the rarity of these events, it's extremely exciting to be involved in these observations. These are the most exciting observations I've seen in my five years of observing the outer planets!"

This really is a extremely exciting discovery. This is also a great example of how amateurs can make real contributions to science. A few weeks ago, a fourteen-year-old discovered a new type of supernova. There are groups of amateurs that study variable stars. Astronomy really is a special field because the wonders of space are there for anyone with a telescope. If you don't have a telescope, find a local astronomy club. Most amateur astronomers want nothing more than to share the wonder of seeing these things with your own eyes. I don't know how long this impact scar will be visible so get out there and see it while you have a chance. Astronomy is by no means the only field that amateurs can make big contributions to. There is no better way to get a appreciation and understanding for the sheer beauty of science, then going out and doing it yourself.

For more information-
Universe Today
NASA
Keck
Image Credit- Credit: Paul Kalas (UCB), Michael Fitzgerald (LLNL/UCB), Franck Marchis (SETI Institute/UCB), James Graham (UCB)

POP Extra: Out in the Field

I've been a little out of touch for the past couple of weeks, and so haven't been able to post. However, it's been worth it: I've been out working in the field. And since I just got back, I thought I'd share my two cents about what goes on out in the middle of nowhere. So, in no particular order, here are my tips, laws, and memories of paleontology out in the field.

• "A clean quarry is a happy quarry": I swear, this maxim is drilled brutally into every person going out into the field. It doesn't matter if you are in a leaf quarry, and dinosaur quarry, or even just out searching for ammonites laying on the ground. Every mentor I've had in the field has mentioned this repetitively. What this means in that, if you make sure there is not a lot of rock debris around the area you are working, you are less likely to damage a fossil. It has been a useful piece of advise. But after the 500 billionth time hearing it, it becomes a little annoying. Even this year, at my 8th field season at this quarry I've been at for the past couple weeks, my supervisor still repeated that at least 5 times.


• Murphy's Law: While not a really a paleontology-exclusive law, it does seem to apply. At pretty much any quarry, when you have to dump a bucket of dirt and rocks down the hill, the wind will invariably change directions to blow as much as possible into your face. This year was easily the worst for everything that could go wrong, going wrong, though. When I arrived at the house used by the workers at this quarry, the sink exploded, the Internet did not exist, the quarry money could not be access, and the shelter tarps for on the hill had been misplaced. I lost about 2 days of field work, simply because absolutely everything went wrong. However, once all the problems were solved, the work itself went without a flaw. I suppose the cosmic balance had to be restored, as we had had too much bad luck in a row.


• Animal Encounters: One thing about being outside, in the middle of nowhere, working on dinosaur bones, is that you do run into animals. Some of these are friendly, and become quarry mascots: small brown lizards, marmots, hummingbirds, butterflies.... Others are much less welcome. Scorpions, snakes, and gigantic wasps and bumblebees in the quarry are among the most concerning animal encounters I've had during my time in the field.


• Field Conditions: Another thing about being in the middle of nowhere is weather. It's generally about 100+ degrees out on the rocks. One particularly memorable day, it was over 140 degrees fahrenheit. My little thermometer broke, and my solid sunscreen melted all over the inside of my backpack. Up until that point, I wasn't aware that sunscreen could melt.


• Patience is a virtue: If you aren't patient, than paleontology isn't for you. I spend hours sitting in the same position, dilligently working very hard rock away from the bones. It can be rather tedious, and it's hard to see progress. However, at a point, that work makes it possible to remove the bone. Seeing the empty space left behind is one of the most rewarding experiences out in the field, even more than discovering new bone. After all, a new discovery means the headache of recording and then attempting to remove it. Taking a bone out means it is no longer an immediate problem. Eventually, it has to be prepared in the museum, but it is currently out of the way.

It probably sounds, at this point, like field work isn't much fun. However, my experiences have always been a lot of fun. Paleontologists are great people to work with, and are often very funny. I recommend, if you are interested, looking into opportunities through your local museum, or online with things like Dig for a Day.

As my mentor says, paleontology is a sort of affliction. It's not a field that pays well, and definitely isn't many people's cup of tea. For those of us bitten by the paleo bug, though, it is a wonderful experience, and a field of science that we just can't get free of.

POP: Collection

Once you have a field site, (as described in Getting Started) then you can get into the fun stuff: collecting the fossils. Collection is sometimes a very simple process, and a fossil is removed from the field in an afternoon. Other times, it is very challenging, taking years to complete.

In general, invertebrate and plant fossils fall under the first category. Invertebrates like ammonites, bacculites, clams, crabs, etc., can errode out of shales and be simply picked up off of the ground. They can also be found in limestones. Often times, if you take a rock hammer to a piece of limestone in a fossil-rich formation, you can find fragments of clams or other invertebrates inside.
Leaf fossils are found in a similar way. Paleobotanists determine a probable leaf site, then create a quarry with pickaxes, until leaves start appearing in the rocks. Then, using primarily rock hammers, they begin cracking open slabs of rock, looking for the fossils. These are then wrapped snugly in toilet paper, and put in cardboard flats to be transported.

Dinosaurs, and some mammals. tend to be much more difficult to collect. These larger creatures are preserved in the rocks, like other fossils, but are composed of many individual bones. These may cracked or distorted by the pressure of the earth and millions of years. Sometimes, the animals will be fully articulated; other times, multiple animals will be found jumbled up in a bone bed. The bones are also too fragile to be extracted with rock hammers and chisels, generally; dental picks and pneumatic equipment are more commonly the tools of choice. It takes hours to days of work to get a single bone ready for removal, assuming there are no complications (such as another bone being directly beneath it). Then, the bone has to be protected in a plaster cast before it can be removed. Eventually, though, a cast is ready to be popped out and taken out of the quarry.

Once fossils are collected, some dissappear into private collections. Many, however, go to a museum, where they are prepared for research or display.

For more information about how fossils are collected, visit the Denver Museum of Nature and Science website, and read the "Excavation" section.

Carnival of Space 112

Just in case you haven't read enough about the moon landings today, this week's Carnival of Space is all about the moon landings. You can find the Carnival at Out of the Cradle.

Google Goes to the Moon

I have always been a huge fan of Google Earth. When they added the ability to explore Mars as well, I was thrilled. I love looking at the space craft panoramas and being able to explore this distant world on my laptop. Today, I discovered Google Moon. The image on the left is a 3D model of the Apollo 11 lander. There are also two guided tours of the moon. I teach astronomy in my "free time." Tools like this are great.
Enjoy.

You can download Google Earth here

Apollo's Fortieth Anniversary: What Does the Future Hold?

It was forty years ago today that Neil Armstrong walked on the moon. Today, many people within NASA and elsewhere are looking back at this historic moment, and forward at what the future holds. In recent years, NASA has received a lot of criticism for not maintaining the amazing spirit of adventure that defined the 1960's. In the 60's there was the political drive to get into space and quickly. The boom in science funding influenced an entire generation. It was that generation that was responsible for the tech boom of the 1990's.
I don't necessarily think we need manned missions to reignite enthusiasm in the space program and science, but we need to push the limits. I think that NASA has become more conservative about what missions they will launch. Let's really work on a sample return mission from Mars, a rover to Venus or Titan, a submarine to Europa. Yes, all of these missions would be extremely challenging. To me, that makes it exciting; that's how we draw in the public. If we get more ambitious, we would lose more missions to failure. When we succeed, we would get amazing new looks into the amazing places around us.

What happened forty years ago changed what we thought was possible. I think that today we all need to admire what we able to accomplish, and look for the next accomplishment to inspire a generation.

Did Jupiter Just Get Hit?

Amateur astronomers play a important role in astronomy. Professionals just can't be watching all of the cool stuff out there, all the time. This recent photo, which has been spreading like wildfire across the Internet, was taken by an amateur astronomer in Australia. There is a lot of speculation that the dark spot at the top could be the aftermath of a large impact. You can see the resemblance to the Shoemaker-Levy 9 impact from 1994 (picture below).

There is still the possibility that is just a weather phenomena. Jupiter's clouds are very dynamic and something like this would not be that surprising. I wish the skies here were clear so I go out with my telescope and see it. If you have a telescope go out and give it a shot. Hopefully over the next few days. and more observations, we will find out what this is. This is science in action, making observations and trying to figure out what's going on.

You can see a larger image here. Times when it will be visible can be seen here.

Why You Should be Skeptical of the News

So far on Scientifica Phenomena we haven't covered any stories about the paranormal or pseudoscience. These topics can be highly controversial, but to understand science I think it's important to understand why some things just don't qualify. If you read a newspaper or watch the news, the reporting on scientific and pseudoscientific issues is often horrible. This is not to say that there are no good reporters out there, but most of them don't have the background knowledge (or don't care enough) to get the story right. The papers and news stations themselves are more worried about profit then content. Unfortunately, this means that most people's understanding of science, and pseudoscience, is skewed.

I found a great example of this inconsistency of modern journalism at Examiner.com. Yesterday (July 17th) the examiner had two stories about the paranormal. One was titled "Ghost Hunting 101: How to hire a paranormal investigator" and the other "Skepticism 101: Do psychic powers exist?". This is one news source reporting two very conflicting stories. The reality is that the Examiner doesn't care about the accuracy of what they publish, so how does the reader tell the difference?

The best thing to do is do your own research. Look for evidence from other sources that don't have a financial motivation. See if there have been any good scientific studies done. Unfortunately, most of us just don't have the time to do that.

One thing to look for is a clear explanation of why they hold there position. In their defense, the ghost hunting article is not about the existence of ghosts. In other articles by the same author (Pamela Grundy), she does try to argue for the existence of supernatural creatures. The only evidence presented is anecdotal (which I talk about here). On the other hand Michael Rosch in Skepticism 101 talks about some tests that have been done of psychic powers. Micheal also give many external links where you can find more information; this is always a good sign.

It is often hard to tell if an article is really showing the evidence or is misleading you. Again, the best thing to do is look for more information. The mass media can't be trusted to always get the story right. The best way to prevent yourself from being mislead and deceived is to be skeptical.

What is Science? (Anecdotal Evidence)

Many pseudosciences rely on anecdotal evidence to support their claim. Anecdotes are a favorite for quack medical cures. The reality is that anecdotal evidence just can't be trusted when you are trying to establish whether or not something is true.

The thing I always think of when someone tries to present anecdotes as evidence is just how fallible our perception and memory are. Many magicians and mentalists tell you up front they have no supernatural powers, yet they still are able to trick our minds into seeing amazing things. Our memories also change over time. Steven Novell, a neurologist form Yale university says "In fact it [the memory] is likely to change in a way specifically to give the story more meaning, while sacrificing factual accuracy."

The bottom line with anecdotes is they are really bad evidence. If you have lots of anecdotes you still don't have any good evidence; you have a pile of bad evidence. It is worth noting that anecdotes can be a good place to start research. When you get into trouble is when they are the end of your research.

For more information check out the Skeptics Dictionary

The LRO Sees the Moon Landers

When the astronauts from the Apollo missions launched off the Moon, the bottom half of the lander was left behind. The bottom half of the lander is only 12 feet across. The really amazing thing is that the LRO will be able to produce pictures two or three times this quality. "Not only do these images reveal the great accomplishments of Apollo, they also show us that lunar exploration continues," said LRO project scientist Richard Vondrak of NASA's Goddard Space Flight Center in Greenbelt, Md. "They demonstrate how LRO will be used to identify the best destinations for the next journeys to the moon."

The first image is of the Apollo 11 landing site. This is incredible timing, as Neil Armstrong's historic first steps on the moon were taken 40 years ago almost to the day (July 20). The lander is hard to see if you don't enlarge it. It is right in the center of the frame casting a long shadow.

This second image is of the Apollo 14 landing site. You can actually see the path to astronauts took across the lunar surface! This is incredible.

I can't wait for the higher resolution photos!

For more photos and information - NASA

Endeavor launch in HD

If you missed the shuttle launch yesterday, you can watch it here in HD.

I love watching these launches. Watch as the solid rocket busters fly off. The energy they get out of those rockets is amazing.

I know it didn't all get in the screen, so, if you want, you can watch it on YouTube. Enjoy!

What is Science? (Natural Explanations)

I have heard a lot of people criticize science because science only allows for natural (and not supernatural) explanations for the universe. This is worth exploring because it used so often, and shows a real misunderstanding for the fundamentals of science.

I think the first misunderstanding is in the use of the word natural. Science is a process of exploring our universe. Our universe, by definition, is everything we can see, detect, or otherwise infer based on evidence. If something exists completely outside our universe we, by definition, cannot explain it using science. You can also think of this another way. Psychic phenomena are considered supernatural because no good scientific evidence has been brought forward to show it exists. If such evidence were brought forward (and replicated) psychic phenomena would become part of the natural world (and no longer supernatural).

The other reason scientists don’t allow supernatural explanations is one of practicality. For thousands of years when a question was raised about the natural world, the answer was always “it’s because of God/the Gods.” This answer is a dead end (and un-falsifiable, which I will talk more about later). In science, saying the flying spaghetti monster did it just doesn’t cut it. In science, we demand explanations based on evidence that will allow us to move forward. The best answers in science have lots of evidence to support them, and generate lots of new questions.

Scientific Unknowns: Venus's Superwind

Venus is a amazing place. With temperatures on the surface that can reach nearly 900 degrees fahrenheit and clouds of sulfuric acid, Venus is not the best vacation spot in the solar system. Like every planet in our solar system, Venus also has its fair share of mystery.

If you comb the Internet for information on Venus, most sites will tell you that the average wind speeds for Venus's top layer of clouds are 300-400 kilometers per hour (about 180-250 miles per hour). The jet-stream on the earth travels at only about 225 kilometers per hour (140 miles per hour). Keep in mind that the Earth is also spinning much faster then Venus. The Earth spins once on its axis every 23.9 hours; Venus takes 5832.5 hours (about 243 days). This super-rotation of Venus's atmosphere is still not understood.

I am currently working with a group of scientists trying to better understand these winds. The really cool thing about all of these unknowns is that there are scientists working on understanding them. Finding out what drives Venus's atmosphere will probably give us a much better understanding of our own atmosphere as well.

Image credit- NASA

Space Shuttle Endeavor Launch on Wednesday?

In the past, I have been reluctant to talk about upcoming launches, and this is why. The reality is that NASA has a very good safety record for their launches, but a very poor record of launching stuff on time. Weather is just too big a factor to be able to launch spacecraft on a timely schedule. The new launch date for Endeavor is Wednesday, at 6:03 eastern time. I hope things finally work out this time.

For more information - NASA

(Note: if you would like for me to continue to keep you updated on launches, let me know and I will. Otherwise, I will probably just talk about them after they're in space.)

Space Shuttle Endeavor delayed another day

Endeavor was grounded again due to the weather. The next launch window is Monday, at 6:51 PM eastern time. Again you can watch it live at nasa.com or on NASA TV. Coverage will start at 1:30.

Source- NASA

What is Science? (Extraordinary Claims Require Extraordinary Evidence)

This statement was made famous made by Carl Sagan. The idea is simple, and something that everyone uses to some degree.

Imagine that someone tells you that they saw a really cool humming bird in their backyard yesterday. That is a fairly mundane claim, so you would probably accept it without much evidence. If someone told you however that they saw a bird with a 20 foot wingspan in their backyard yesterday, you would probably want some evidence. You might ask for photos or some other kind of physical evidence. The more extraordinary the claim, the more extraordinary the evidence must be.

This is a great thing to keep in mind when you are trying to see if a story is true or not. The idea that aliens are visiting us from another planet, for instance, is a amazingly extraordinary claim, yet the evidence is all blurry photos, anecdotal reports, and anomalous radar blimps (I might go into more detail in a latter post). Scientists often make extraordinary claims, like being able to turn urine into energy, but they provide the evidence to back up their claims. This is one of the really important differences between science and pseudoscience, and why science is able to deliver the goods.

Shuttle Launch tomorrow

The launch of space shuttle Endeavor has been postponed to tomorrow evening at 7:13 eastern time. Two earlier launch dates in June were scrapped due to a hydrogen fuel leak. Now that problem seems to be solved, but today's weather has pushed back the launch one more day. Crews at Kennedy Space Center are now checking to make sure that the launch pad and Endeavor were not damaged by any of the lightning strikes. "We've seen nothing so far that shows anything affected any of the systems," said Mike Moses, chairman of the pre-launch Mission Management Team. "We need to be 100 percent confident that we have a good system across the board." The weather should be better tomorrow and hopefully Endeavor will finally get off the ground.

When the launch does happen you can watch it live on NASA TV at your home or at http://www.nasa.gov/home/index.html. I highly recommend it if you have the opportunity.

Source- NASA

Waste to Energy

Alternative energy is a big topic right now. Solar, nuclear, wind, water, hydrogen... anything that can generate power and isn't a fossil fuel is being discussed. So, I suppose that it shouldn't be too suprising that scientists from Ohio University have developed their own alternate energy: pee power.

This energy source is a very cheap way of producing hydrogen. Nickel-based electrodes can collect the hydrogen in urine by debonding it from nitrogen in the urea molecules. It takes less electricity to debond this hydrogen from nitrogen than it does to debond water (0.037 V vs. 1.23 V).

Hydrogen energy is a major contender in the alternative energy field. A hydrogen fuel cell is a very efficient means of producing electricity. (Click the image on the right to see how it works.) Unfortunately, they are currently expensive to build, and so are not commonly used. However, hydrogen could eventually be used to power cars, provide electricity to areas that can't access a power grid, and power day-to-day technology like computers and cell phones.

So, the technology isn't yet to the point where you should start collecting your pee. But, in the future, this may become a way to deal with both waste disposal and energy production. It's a neat, if somewhat peculiar, idea.

Credit: Discovery News

For more information about hydrogen, visit the EIA page.

Dinosaurs Down Under

Today, Australia is the home of some of the wierdest animals on the planet. Suprisingly, though, it's fossil record is very incomplete. There are practically no fossils there, compared to continents like South America and Africa, which are about the same size as Australia. There is one formation in Queensland, however, that has started turning out numerous finds. Recently, they found a jackpot: not one, but three new dinosaur genera. Two of these are massive sauropods; the third is a therapod carnivore.

The carnivorous dinosaur, Australovenator wintonensis, aka "Banjo," is like Australia's version of a Velociraptor: light, agile, and deadly. Unlike Velociraptor, which is about 3 feet tall, however, "Banjo" is much larger. It belongs to the carcharodontosaurs, the largest carnivorous dinosaurs to walk the earth.

The two sauropod species are also some of the largest of their kind. Both Witonotitan wattsi (“Clancy”) and Diamantinasaurus matildae (“Matilda”) are titanosaurs, the largest dinosaurs to ever exist. "Clancy" might have been similar to a modern giraffe; "Matilda" was built more like a modern hippo.

The dinosaurs are about 98 million years old, living in the mid-Cretaceous period. They help fill in a few of the gaps in Australia's weak fossil record.

Credit: Science Daily- Triple Fossil Find Puts Australia Back on the Dinosaur Map

The Farthest Ever Supernova Discovered

Researchers from the University of California, Irvine, discovered the farthest supernova. The new technique they used involved stacking many images on top of each other to bring out dimmer objects. The supernova they saw was around 11.4 BILLION light years away! Jeff Cooke, McCue Postdoctoral Fellow in physics & astronomy, said, "The universe is about 13.7 billion years old, so really we are seeing some of the first stars ever formed".

A light year is unit of distance. It is how far light travels in one year. Light is really fast; in one year it travels about 5,878,786,100,000 miles (almost 6 trillion). The other cool thing is that because it takes time for the light to get to us, we are looking back in time. A supernova is the explosive death of a large star as it runs out of fuel. This supernova was part of the first generation of supernova ever.

Source- UC Irvine

Image Credit- NASA/Swift/Skyworks Digital/Dana Berry

What is Science? (The Method)

Here we cover a lot of new science stories, but I wanted to back up for a second and talk about what science is. This is really important because if you don't know what science is, it can be very hard tell good science from pseudoscience. To start with, let's take a look at the very often oversimplified and misunderstood scientific method. (Note: click on the image to enlarge)

To start with, you have to make an observation. This is just finding something that draws your attention. The observation could be anything from the lines in a sedimentary rock to an inconsistency in two existing ideas.

Next, you form your question. This sound really easy, but the question has to be specific and testable. Really big questions have to be tackled through many little steps. "What is life?" is too vague to be testable, and the real problem is we only have one example of life (the Earth's biosphere), so there's just not enough data. What scientists could ask is "What are the unique characteristics of different organisms that separate them from non-living things?".

Then we have maybe the most important part, forming a hypothesis. A hypothesis is a kind of educated guess. The most important thing about a hypothesis is that it makes predictions. Any guess that doesn't make predictions is untestable, and therefore not science. A recent example of this was the Enceladus controversy. The hypothesis is that there is an ocean under the ice on Enceladus. One of the predictions from this is that there will be sodium in the plumes of water if there is an ocean.

The next step is to test your hypothesis. Carl Sagan said it well: "There are many hypotheses in science which are wrong. That's perfectly all right; they're the aperture to finding out what's right. Science is a self-correcting process. To be accepted, new ideas must survive the most rigorous standards of evidence and scrutiny."

Once you confirm your hypothesis, other scientists must confirm your results. If they can't, you have to figure out why you are getting different results. This step prevents people from making up research, and having it contaminate the body of knowledge science builds. If no one can replicate your work, it will eventually just be discarded.

If your idea passes all of these steps, it will start to be accepted by the scientific community. The more evidence for an idea there is, the more support it will have among scientists. This is where you would find theories like gravity, germ theory of disease, and evolution. Theories are not the same thing as hypotheses. Theories in science are well supported by a large body of evidence, but are not immune to change in the face of new evidence.

This is very basic overview of how science works. In practice, things are rarely this clean. The key to a scientific claim is making predictions, and finding the evidence. Everything else falls in place around that.

The Wonders of GM Crops

Genetically Modified (GM) foods get a lot of bad press and are often linked with many negative health effects. The reality is that there is no scientific evidence against GM food. They are also some of the most rigorously tested food products. This doesn't stop groups like Green Peace from adamantly fighting against GM food.

The reason GM food is so widely used is because it is made to have advantages. GM crops often require less fertilizer, less pesticides, and are less demanding on the soil. Science Daily announced today that scientists in Australia have come close to creating GM crops that could grow in areas with high salt concentration. "Salinity affects the growth of plants worldwide, particularly in irrigated land where one third of the world's food is produced. And it is a problem that is only going to get worse, as pressure to use less water increases and quality of water decreases," says the team's leader, Professor Mark Tester.

The basic idea is they have found a way to create plants that filter out the salt in the roots. The world's population is not getting smaller. With a growing population we are going to need genetically modified foods more and more. It is really important that people understand that GM food is not the villain our culture sees. GM food is a hero in disguise.

Source- Science Daily

Scientific Unknowns: Mercury's Black Eye

Mercury is a dead world. It has no notable atmosphere, no plate tectonics, and no volcanism. The only thing that reshapes Mercury's surface now are impacters, crashing into the surface and leaving craters in their wake. Yesterday, on NASA's Astronomy Photo of the Day website, they had a picture of one of these craters. In this picture you can see a dark substance at the bottom of the crater.

The first thing we need to rule out is it being a shadow. Notice that there are no noticeable shadows in any of the other craters. That's because the sun is at zenith. This means if you were standing on Mercury the sun is right overhead. This rules out the shadow theory.

If you are familiar with geology, you know that there are lots of different kinds of rocks and metals that are a dark black. The question is which one is it, and where did it come from.

It could be that whatever hit Mercury was made of this weird material. It could also be that

when the surface was impacted material from under the surface was exposed. Other dark rocks have also been discovered by the Messenger spacecraft. One of these is this ring of black

material. The first picture is interesting because it is the darkest. One of Messenger's science goals is discover what this black stuff is. Go Messenger!

Source- APOD

The Sun Fires Up for the 4th

For the last few years the Sun has been really quiet. Sunspots are Earth-sized dark spots on the sun. Sunspots are created when magnetic field lines "bunch up" on the surfaces of the sun. The spots are dark because they are slightly cooler then the surrounding surface. Sunspot activity goes through a 22 year cycle. Every 11 years the sun fluctuates from having lots of sunspots to very few or none at all. The "Solar Minimum" that we are in right now is lasting longer and with even fewer sunspots then predicted.

This weekend SOHO (Solar and Heliospheric Observatory) spotted a new sunspot. Maybe we will finally be coming out of this minimum.

Remember that those "little" spots on the sun are the size of planets!

Redefining "Hard as a Rock"

It's commonly thought that diamond is the hardest natural material. On the Moh's scale of hardness, with 1 being an extremely soft rock and 10 being extremely hard, diamond ranks at 10. However, there is new evidence that there are materials out there even harder than diamond.

The first of the two materials that beat diamond is called wurtzite boron nitrade (w-BN). It was compressed, changing the bonds between the atoms. This created a super-hard structure, harder than diamonds. It reached a strength of 114 billions of pascals (GPa) under these indentation conditions. Diamond, in comparison, has a strength of 97 GPa. A second material, lonsdaleite, is even stronger. Under the same indentation process, it compressed to a strength of 152 GPa, hugely stronger than diamond.

The reason why w-BN and lonsdaleite (the structure of which is in blue above) are so strong is because of slight differences between their atomic structures and that of diamond (the structure of which is in red below). When compressed, these bond become extremely strong. Lonsdaleite is the strongest because of its carbon-carbon bonds, like diamond. W-BN has a similar structure to lonsdaleite, but the boron-nitrogen bonds are not as strong. These materials, created in an indenter, can be a model for the technique creating other super-hard materials. Diamond has not completely lost its throne, however. Neither w-BN or lonsdaleite are easily produced in mass quantities. The nano amounts formed are not even enough for extensive experimentation, much less common use. Still, the materials, and more importantly their method of production, open a broad realm of opportunity. Super-hard materials can be created to be stable at high temperatures, which diamonds are not. They can also be tested as conductors and superconductors, which more common super-hard materials like diamond are not. The technological applications will be interesting to see.

And no longer is diamond the epitome of strength. It's still significantly harder than most substances, but is not the only super-hard material out there.

Source: Physorg.com "Scientist Discover Material Harder than Diamond"

It Snows on Mars

Most people think that we learn everything from our robotic explorers while they are still working. The reality is that the spacecraft we send to these distant worlds send back tons of information. Sometimes it's months or years after the spacecraft has died that we get the really cool discoveries. This is the case here. In this week's issue of Science, four papers were published on the data returned from the Phoenix Mars lander.

Phoenix spent five months on the surface of Mars. It was in the polar region of Mars, trying to give us a better idea of the geology and climate. One of the papers published in Science shows evidence of snow on Mars. Peter Smith, the Phoenix Principal investigator, said, "Frost was predicted, but snowfall was quite a welcome surprise."

These scientists found that the water was freezing out of the clouds at night and then sublimating (turning from ice to vapor without turning to a liquid) in the morning. This discovery was made with the LIDAR on Phoenix. The LIDAR sends a laser burst straight up, and observes how the light scatters of dust and ice. The researchers also found water clouds that were imaged by Phoenix. This is incredibly exciting. Phoenix may have died nine months ago, but the discoveries keep pouring out.

Source- Universe Today

Science

POP: Getting Started

Now that I've discussed the principles of paleontology, let's really take a look at the processes of doing paleontology.

There are quite a few steps between discovering a fossil and getting it in a museum. In fact, there are quite a few steps before a researcher can even go out and find a fossil. First, they need an idea of where to look. By understanding the geology of an area, paleontologists can predict what fossils might be found in what layers. The Morrison formation in Colorado, for example, is full of dinosaurs and fossil footprints. The Pierre shale, on the other had, has mostly ocean invertebrates like clams and crabs, as it was deposited when Colorado was covered by an inland sea. There is no point in look for fossil leaves in a basalt, for instance: basalt is the remains of an ancient lava flow. However, fossil leaves are often found in mudstones, especially when there are coal layers, as these are the remains of ancient peat bogs. So, paleontologists need a good understanding of the geology in the area before even heading out the the field.

Another important step, though not the most interesting one, is getting land permission and grants. Without money and the permission to dig on a plot of land, it doesn't matter if there is a perfectly preserved Tyrannosaurus family- a scientist can't go excavate it. Thus, grant writing to get the funding, and getting permission to collect, are big steps before heading out to the field.

Prospecting itself occurs when the paleontologists actually get out to the field. This process varies a lot. Sometimes, they arrive at a site and the fossils are right there. This happens a lot at construction zones. When crews find fossils where they are excavating, they often call an expert at a museum about it. A wonderful fossil leaf site outside of Castle Rock, Colorado, was found this way. However, with these sites, there is a big time deadline. Construction is on a schedule, so any work on the site by paleontologists has to be quick, and may not remove all the site has to offer. There is a Tyrannosaurus with an address for this reason; the house had to be built, so most of the dinosaur was left in the ground.
Other times, museum experts get a tip from someone that fossils are found in an area. A kid might bring in ammonites from his dad's ranch, for instance, or a hiker might show up with a chunk of dinosaur bone she found on public land. These tips let paleontologists investigate a particular site of interest, without having to search around for it so much. This is probably the most common method of finding fossil sites.
A third method is true prospecting. I've only seen this used for invertebrates and leaves before. Basically, scientists go to an area with the formation they expect to find fossils in. They find a site that looks promising, then search the rocks for fossil traces. There might be bellumnites littering the ground in one area, which can then be collected. For leaves, there might be just one rock, initially, with a part of a leaf on it. Paleobotanists then take pickaxes to the wall, discovering a cache of leaves hidden for millions of years in the rock.

Regardless of how a site is found, the researchers can then move on to excavation.

For more information on how fossil sites are found, take a look at this site, created by the Denver Museum of Nature and Science.

Spectroscopy (Decoding the Light)

In my last spectroscopy post, I talked about all of the different colors, or types, of light. Now for the cool stuff. Using light, we can tell what something is made out of. For example scientists have found water and organic molecules in the atmospheres of planets orbiting other stars, just by looking at the light.

Figuring out what something is made of can actually be quite simple, though its usually not. Basically ,what scientists do is break down the light. By this, I mean that they take the light and spread it out into a rainbow. When you do this, little lines will appear, or lines will be missing. These are called absorption and emission lines. By looking at the spacing between the lines, we can tell what something is made of. To get a better idea of how this works, take a look at this site. You can see how each element has a distinct fingerprint of lines.

So, if a planet has water in its atmosphere, we see the set of lines for water. If a cloud of interstellar gas is made of hydrogen, we see the lines for hydrogen. This is used constantly by astronomers, like in the recent debate over Enceladus's ocean. This is a amazing technique because it gives us a window into the composition of our universe.

For more information- Astronomy notes

Astronomy Cast