Asteroid Vesta has revealed itself as colorful, diverse – and even older than our Earth — in the first-ever orbit of an object in the asteroid belt by a space probe. NASA’s Dawn mission orbits the massive asteroid Vesta through August of 2012. Carol Raymond is the Deputy Principal Investigator of the Dawn space mission. She announced early Dawn findings at a May 2012 press conference from NASA headquarters. She told EarthSky:

Asteroid Vesta. Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn’s data have allowed the history of Vesta to be defined. It formed within two million years after the first solids formed in the solar system — before Ceres formed, before the terrestrial planets formed.

Video: Glide over Vesta in 3D

Scientists consider asteroid Vesta to be a protoplanet, one of roughly a hundred space seeds that clumped together from dust and other space rocks to eventually grow and form the planets. Raymond said:

We now know that Vesta is the only intact, layered planetary building block surviving the very earliest days of the solar system.

Here’s more about the landscape of Vesta: Dawn spacecraft reveals landscape of Vesta

This early data show asteroid Vesta to be like a three-layer cake, with a concentrated iron core, a silicate mantle, and a thin crust of basalt. In this way, she said, it’s like the Earth, the moon, Mercury, and Mars. What’s more, about one in twenty meteorites are now confirmed to be pieces of Vesta. These meteorites result from a gigantic collision that left a crater on Vesta the size of the main island of Hawaii. Raymond told EarthSky:

Vesta is special because it survived the intense collisional environment of the main asteroid belt for billion of years, allowing us to interrogate a key witness to the events at the very beginning of the solar system.

Listen to the 90-second EarthSky interview with Carol Raymond on asteroid Vesta, at the top of the page.

Scientists from Italy and Germany announced in early May 2012 that they have found the world’s oldest known human blood in a 5,300-year-old mummy. Materials scientist Marek Janko of the Center of Smart Interfaces at Darmstadt Technical University, Germany was on the science team, and he told EarthSky:

Our main finding is that blood cells can be preserved for 5,300 years and even detected after such a long time.

These researchers used cutting-edge nanotechnology including atomic force microscopy and light-based Raman spectroscopy to verify the shape and molecular composition of the blood. The scientists published their results on May 2, 2012 in the Journal of the Royal Society Interface.

Oldest known red blood cells, imaged by atomic force microscopy.

The Iceman - nicknamed Oetzi - whose bones were found in 1991 as he might have looked while alive. This reconstruction was displayed at the Archeological Museu of Bolzano during an official presentation of the reconstruction in 2011.

The scientists analyzed what’s called the Iceman, an exquisitely preserved mummy discovered frozen in a glacier. Two hikers in the Ötztal Alps along the border of Austria and Italy came upon the mummy in 1991. Since then, scientists have analyzed the Iceman – who has been nicknamed Oetzi – for clues about how he lived and died. They now believe, for example, that Oetzi died after being shot in the back by an arrow. Despite his icy preservation, no blood had been found in The Iceman – until now. This recent research team examined the areas near two wounds, one on the Iceman’s right hand and one in his back where an arrowhead was lodged. Janko told EarthSky:

By analyzing the red blood cells which we find, either on his hand wound or within the arrowhead wound, we could find the characteristic hemoglobin spectrum. Additionally, in the case of the red blood cells from the arrowhead wound at his back, we could determine another protein, fibrin, characteristic of the coagulation of blood, and the formation of a blood clot.

The Iceman, world's oldest mummy, discovered frozen in glacier near border of Austria and Italy. © South Tyrol Museum of Archaeology

In other words, the fibrin found on the Iceman indicated the arrow wound on his back was relatively fresh and most likely the fatal wound according to Janko. This forms exciting new evidence for the weapon in what is the oldest known crime scene known to science. Janko said there are other good reasons to study mummies like the Iceman:

Those remains can really give us some information about our ancestors, not only telling us what people used to eat in former times but even for example what kind of diseases they had. And those information can even make it possible to create medicines against different kinds of disease by knowing how they evolved.

Scientist examine the remains of the past to develop new medicines, said researcher Marek Janko. © South Tyrol Museum of Archaeology

Bottom line: Scientists have found the world’s oldest known blood in a 5,300-year-old mummy, known as the Iceman. Earlier scientists had determined that the Iceman likely died from an arrow in the back. These scientists, including materials scientist Marek Janko of the Center of Smart Interfaces at Darmstadt Technical University, Germany, were able to isolate blood from the Iceman’s ancient wounds. Janko told EarthSky that analyzing the ancient remains of the Iceman might help scientists today develop new medicines by studying how diseases evolve.

David Stuart on the Mayan calendar and 2012 doomsday predictions

Scientists discover an unusual stone circle in British Columbia

Climate change might have driven turning points in human evolution, according to an April 2012 gathering of scientists hosted by Columbia University’s Lamont-Doherty Earth Observatory (LDEO).

What’s more, scientists have within their grasp the ability to answer this question by filling gaps in the fossil record and reconstructing past climates. That’s according to LDEO paleoclimatologist Peter B. deMenocal. He told EarthSky:

One of humankind's greatest hits: the two-sided stone cutting tool coincides with rise of genus Homo. Acheulean Biface from Saint Acheul, Amiens, Somme, France.

The linkage between faunal change and climate change really has to do with a very basic observation, which is that organisms are fundamentally linked to the resource availability of a given landscape. As the energetics of the landscape, the utility of the landscape changes, the fauna have a series of options that that they can either adapt or become extinct.

The appearance of genus Homo about 2.5 million years ago and the later development of a two-sided stone blade tool set a million years later mark turning points of human evolution linked to climate, said deMenocal. He said:

We’re now beginning to place these evolutionary change points within the context of past environmental change in Africa to examine this question of whether the evolutionary changes themselves were coincident and perhaps linked to changes in the environment in East Africa.

The dry grasslands of East Africa today were once canopied woodlands, said deMenocal.

Those grasslands didn’t come into being until almost two million years ago. Actually, the first appearance of that really open dry, arid, vegetation coincided in time almost exactly with this Acheulian tool kit, this very sophisticated bi-facial rock blade.

It’s this transition toward more open conditions and more variable conditions that is thought to have been the motor behind some of the evolutionary changes that occurred at this time.

'The history of human evolution really takes place in East and South Africa several million years ago,' said Peter deMenocal. Image credit: Smithsonian

What’s more, Homo errectus – the branch from which modern humans emerged – came out of Africa at roughly this same time two million years ago. DeMenocal added:

What really leads to new life forms emerging and new adaptations emerging comes from the challenges climate change presents. There are winner and losers to that process. There are things that go extinct and there are new organisms that pop up and become successful in a new climatic regime. It’s really climatic instability that leads to the best adaptations to a given environment, because it provides a shake-up the resources for a given environment.

The April 2012 symposium at Columbia University comes off the heals of a 2010 report by the National Research Council and a February 2012 article by deMenocal in Science magazine that examine the premise of whether climate change shaped human evolution. There simply isn’t enough evidence to firmly establish this link, but the scientific tools exist today to get answers, said deMenocal. This question has relevance even to what’s happening today, he added.

The lesson that we take home from the study of how climate change may have changed early human evolution is a recognition of the larger truth, which is actually echoed throughout the geologic record of the co-evolution of life on the planet and climate change — is that there are many, many examples of extinctions linked to events of massive environmental change.

And so if we take the biggest possible view of this, the story of life on Earth is really one that is a dance between the co-evolution of life on the planet and the physical environment, the climate. So as climate changes in the future, one has to expect, with one’s eyes open, that aspects of the living world will respond to the climate changes that are underway.

Bottom Line: In an EarthSky interview, paleoclimatologist Peter B. deMenocal spoke about how climate change might have driven turning points in human evolution. The rise of genus Homo and stone tools coincides with climate change two million years ago in East Africa. It’s too early to tell for sure, said deMenocal, but scientists have the ability today to start answering whether this link is solid.

Mysterious Red Deer Cave people found in China

Evolution might favor men who misinterpret sexual cues

Chris Field reports extreme weather on rise from climate change

A professor of chemistry at the California Institute of Technology, Jacqueline Barton received a National Medal of Science in 2011 for her discovery that cells use the double strands of the DNA helix like a wire for long-range signaling among proteins within a cell. Her research holds promise for understanding how cells detect and repair DNA defects – related both to ordinary conditions like aging – and to diseases like Alzheimer’s and cancer. This podcast is part of the Thanks To Chemistry series, produced in cooperation with the Chemical Heritage Foundation. Generous sponsorship support was provided by the BASF Corporation. Additional production support was provided by The Camille and Henry Dreyfus Foundation, DuPont, and ExxonMobil. Jacqueline Barton spoke to EarthSky’s Jorge Salazar.

On October 21, 2011, you received a National Medal of Science for discovering that DNA acts like a wire in a cell. Tell us about that.

First of all, it was an extraordinary honor. I represent all the people who work with me – the graduate students and post-docs who really carry out the work.

We think about DNA usually as the library of the cell. It encodes all the information that makes us what we are.

National Medal of Science winner Jacqueline Barton via LA Times

But it also turns out that when you look at the chemical or molecular structure of DNA – that spiral staircase we call the double helix – you find the steps of the spiral staircase stacked one on top of one another. It turns out that the DNA double helix looks a lot like solid state materials that are quite conductive.

Very soon after Watson and Crick first described the structure of DNA, chemists started asking – does this structure have the characteristic of being conductive? That was over 50 years ago.

About 20 to 30 years ago, chemists began being able to synthesize a little piece of DNA – to know exactly what’s connected to what.

We attached little molecular probes to either side of the DNA double helix to ask whether or not you can shoot an electron from one side of the DNA to the other side of the DNA. And that’s how it all started.

Then what happened?

At first, we thought about DNA in terms of its chemical characteristics. We found that electrons and “holes” could move through DNA. We usually think about DNA as “the library” because DNA encodes the RNA. The RNA is sort of like taking a Xerox copy of what’s in the library. Then from the RNA you go through the ribosome machine. And you make proteins. The proteins that are made are encoded by the sequence of base pairs in DNA.

The nuclei of all our cells are filled with three billion base pairs of information in the DNA. But some of our cells have to become, say, a nose cell. Those cells have to make certain proteins get expressed. Others of our cells have to make other proteins get expressed. And all that information is in the DNA library.

DNA double helix.

What happens, let’s say, when a cell is under stress? It has to activate a response to that stress. We’ve been finding that actually the information has to get coordinated across the DNA library because a lot of things have to happen. A lot of proteins have to get made.

We thought maybe there’s signaling across the nucleus of the cell – across the DNA-containing genome. Some of that might actually be happening by using DNA as a wire.

What do you mean by that? How can DNA be like a wire?

Your DNA is getting damaged all the time, especially if you don’t, say, eat your broccoli. When the DNA gets damaged, that damage has to get fixed or else that information in the DNA library can’t be used anymore. In each of our cells, we have this exquisite repair machinery. Little proteins are constantly sifting through your DNA to find mistakes and fix them.

We found out that DNA can be a good wire. But it’s only a good wire if all the bases are stacked on top of each other – these steps on the spiral staircase – and if the DNA isn’t damaged. If there is a little mistake in the DNA, then it’s not a good wire anymore.

It’s like a stack of copper pennies. And that stack of copper pennies can be conductive. But if one of the pennies is a little bit awry – if it’s not stacked so well – then you’re not going to be able to get good conductivity in it. The same is true in the DNA double helix.

Let’s go back to thinking about our DNA becoming damaged all the time – how those repair proteins have to find those mistakes in the three billion bases of DNA. We think that what happens is that nature uses DNA like a wire. It’s sort of like two telephone repairmen trying to find a mistake in the line. If they can talk to each other, if these repair proteins can talk to each other across the DNA, then the DNA is just fine. So they don’t have to repair that region. And they can go someplace else.

But if there’s a mistake in the DNA, then they can’t talk to each other so well.

From starting out over 20 years ago in synthesizing little pieces of DNA – and seeing if we can shoot an electron up or down it – we’ve come now to the point of saying nature uses DNA like a wire for long-range signaling and for finding mistakes in the DNA.

What inspired you to become a chemist?

I like being in the lab. When I was in high school, I took a lot of math courses. When I went to college I thought I’d try a chemistry course. The lab part of the class was really exciting. It got me hooked. And it gave me a way to combine my mathematical perspective with thinking about real-world problems.

At the beginning, it’s detective work – having a puzzle, a problem to solve. Doing a reaction in the lab and seeing things change colors and then isolating a product and finding out what it was. That was exciting.

As I got more and more into it, I started getting involved in research. Then there are all sorts of interesting things to think about. You’re learning things that no one ever knew before.

Listen to the 90-second and 8-minute EarthSky interview with Jacqueline Barton on the insights of today’s chemists on the repair of DNA defects – related both to ordinary conditions like aging – and to diseases like Alzheimer’s and cancer (see top of page). For this and other free science interview podcasts, visit the subscribe page at EarthSky.org. This podcast is part of the Thanks To Chemistry series, produced in cooperation with the Chemical Heritage Foundation. EarthSky is a clear voice for science.

More in the Thanks to Chemistry series:

Robert Langer on targeted drug delivery for future medicine

Nina Fedoroff on science for global agricultural challenges

Joseph DeSimone on being an inventor

George Whitesides: The world that we live in is chemistry

Nate Lewis on artificial photosynthesis

Frank Hill is an astronomer at the U.S. National Solar Observatory. Last summer (June, 2011) Hill and colleagues announced their conclusions that sunspot activity might be headed for a dramatic drop in activity, beginning around the year 2019. The sun normally follows a cycle of activity lasting about 11 years. The current cycle, Cycle 24, is now heading towards its peak. Frank Hill and colleagues are looking toward the next cycle — Cycle 25. Based on data showing decades-long trends, they are suggesting its peak might be delayed or that it might not have a typical peak in activity at all. Hill spoke more about the recent sunspot study with EarthSky’s Jorge Salazar.

Are you familiar with media reports that have gotten this story wrong?

Yes, actually. It seems to me that a lot of reports have come out and said that we have predicted a new ice age. That is making the leap from low sunspot activity to cooling. We did not predict a little ice age.

What we predicted is something that the sun will be doing, not what the Earth’s climate will be doing. That has been the major inaccuracy that I have seen in the media at this point.

You studied jet streams below the surface of the sun. What were your main findings?

For 16 years, we’ve been observing the inside of the sun using a technique called helioseismology. The sun is filled with sound waves — acoustic waves — that penetrate and travel all the way throughout the sun. They are visible when they strike the surface of the sun from the inside, making the surface move up and down.

Using this data, we can infer the motions of the gas inside the sun.

The solar disk, showing a moderate number of spots. Image Credit: NASA

And we have found that there is a jet stream, which had been observed previously on the surface in 1981, that is very tightly timed to the solar cycle.

This jet stream typically first appears at a high latitude on the sun, near the solar poles, approximately 10 to 12 years before the start of the solar cycle. It then moves first toward the poles, and then another branch appears. It moves towards the equator. We should be seeing the poleward branch of this flow for Cycle 25. That’s the next cycle of sunspots after the the one that we are in, which is Cycle 24. We should have seen that flow back in 2008, and we still have not seen it. And so this leads us to believe that that there is something different about Cycle 25 than we have previously seen.

When the sun has sunspots on it, the sun is a little bit brighter than when there are not. So if there’s a lack of sunspots, then the sun is a little bit dimmer. By a little bit, I mean one tenth of one percent. It’s a very small fraction.

What does this all mean?

It could mean a range of things. It could mean that the next sunspot cycle, after the current one, could be delayed by two to five years, at least, and perhaps longer.

Frozen Thames, circa 1677. Artist unknown. Wikimedia Commons.

Or at the other extreme, it could mean that there are no sunspots appearing at all for an extended period of time. We could be entering a situation similar to the Maunder Minimum, which was a period of 70 years or so, from 1645 to 1715 — where very few visible sunspots were observed. [Editor's Note: The Maunder Minimum -- a period of decreased activity on the sun -- is often said to correlate roughly in time to what is sometimes called the Little Ice Age, a period of unusually cold weather in northern Europe, during which people were said to ice skate on the Thames.]

The Maunder Minimum has been connected to the Little Ice Age, anecdotally. However, there are some indications that the connection with the Little Ice Age might not be as strong as some people claim. It probably depends on how you define Little Ice Age.

But in some measures you can say that the Little Ice Age is thought to have occurred 100-300 years before the Maunder Minimum itself. So while part of it coincided with the Maunder Minimum, not all of it did.

So it’s not clear that there really was a cause and effect. It’s definitely a very gray area, and of course we don’t have very good data on it because it happened so long ago.

What do you expect to happen now, with activity on the sun?

In 2013, we expect to see a maximum of the current solar cycle, which is Cycle 24. The next solar cycle, Cycle 25, should start about 2019 or 2020. What we are claiming is that it may not start in 2019 or 2020. It might be delayed until 2025 — or even longer. We can’t tell yet.

Close-up on a sunspot. Image Credit: NASA

The evidence is this. The jet stream flow that we are observing inside the sun — as well as with helioseismology — is very tightly correlated with the timing of the solar cycle. For instance, you might have heard of the long, deep minimum that we just emerged from — between Cycles 23 and 24. That minimum was approximately 1.5 years longer than we normally experience. We found that the jet stream inside the sun — which we call the torsional oscillation and which migrates from high to low latitudes on the sun — was migrating at a much slower rate than it had in the past. It took about 1.5 years longer to reach the latitude at which sunspots begin to appear.

And that made us realize that observing this phenomenon could provide a clock, a future predictor of what will be happening for the overall solar cycle itself.

Listen to the 8-minute and 90-second EarthSky interviews with Frank Hill on the predicted decrease in solar activity — and inaccurate media reports that it means a period of cooling for Earth — at top of page.

In March, 2012, the European Southern Observatory (ESO) announced new work suggesting that rocky planets – not much bigger than Earth – are very common around faint red stars in our Milky Way galaxy. Not only that, but these rocky worlds commonly lie in the habitable zones – orbital zones around stars within which liquid water, and therefore life as we know it, might exist – says ESO. And that’s really something to think about!

EarthSky spoke with Stéphane Udry of the Geneva Observatory in Switzerland. He told us:

It’s easier to detect habitable planets around low-mass stars, these red dwarfs, than around stars like the sun. And on top of that, those stars are by far the most numerous ones in the galaxy. So we have a sample of such stars. We look for planets. And we are finding that around ten percent of them, roughly, they are rocky planets. And as there are hundreds of billions of those stars in the galaxy, we conclude that there are tens of billions of planets that are rocky around those stars in our galaxy.

Artist's conception of the surface of a world in the habitable zone of its star, where liquid water can exist. Image Credit: ESO/L. Calçada

Dr. Udry and an international team of astronomers used what’s called HARPS, the High Accuracy Radial-velocity Planet Searcher of the ESO. It detected tiny redshifts of light from a sample of red dwarf stars in our galaxy. This redshift indicates the tug of a planet. Red dwarf stars, said Udry, are fainter and cooler than our sun. Udry said:

What we call the habitable zone, the zone with the good temperature for liquid water to exist around the star is closer to the star than in the case of the sun. And for us, with our technique of detection, we are more sensitive to planets that are close to their stars.

The ultimate goal of this planet-hunting, said Udry, is to find a planet like Earth out there.

We are on our way to detect places like the Earth, where life could be developing. So all our work is on a road that in the end will lead us to the detection of life somewhere else in the universe.

Bottom line: An international team of astronomers working with the European Southern Observatory announced n March, 2012 that there might be billions of rocky planets in the habitable zones around red dwarf stars in our Milky Way. Since red dwarfs account for 80% of the stars in the Milky Way, that might be a lot of planets!

Weather extremes worldwide, such as droughts, floods, and heat waves, are on the rise over the past 50 years. What’s more, they’re linked to climate change. That’s according to a special report by the Intergovernmental Panel on Climate Change (IPCC) released in March 2012 and authored by 220 scientists and experts from 62 countries. EarthSky spoke with ecologist and lead author Chris Field of the Carnegie Institution for Science at Stanford University. He said:

Extreme Weather 101 via

We know from looking at thousands of scientific papers that climate extremes are increasing, some important extremes. And that includes extremes of high temperature, extremes in the length and severity of droughts, extremes in the amount of precipitation that’s falling in the heaviest events, and extremes that are associated with high sea level.

Economic losses from extreme weather events have also risen, mainly because people have put more stuff, buildings and roads, in harms way such as floods and hurricanes, said Field.

Loss of life from weather extremes can be avoided by knowing the risk and taking precautions. He gave the example of two different cyclones. One hit Bangladesh in 2007 and killed about 3,000 people. Another cyclone hit Myanmar in 2008 and killed over 100,000.

The big differences between the hundred thousand lives lost in Myanmar and the 3,000 lives lost in Bangladesh was that Bangladesh had made a series of smart, low-cost investments. Some of those were simply raised plots of ground where people could bring livestock and property to get it above the storm surge. Some of them were structures, where people could go in order to be protected from the storm.

And some of the most effective investments that Bangladesh made were simply making sure that word got out when there was a storm predicted. People knew about it and they could go to higher ground. Or that, when a storm was on the way, people knew that they should be checking on friends and neighbors and relatives, and there were neighborhood organizations that got the word out and got people to safety. That kind of step makes a big difference and it doesn’t necessarily cost very much.

Image Credit: DVIDSHUB

Field said that the climate-related risk of extreme weather is worldwide. He said:

When we looked at the scientific literature on climate extremes and disasters, one of the things that jumps out most prominently is that essentially, every part of the world is subject to some kind of climate-related risk.

In some areas, the big risks are associated with a lack of water, droughts. In other areas, they’re associated with too much water, with risks that generate floods. And in other areas, the primary concerns are temperatures that are too high.

The really striking thing is that there’s the potential for climate extremes to occur everywhere. And there’s the potential for disasters to occur everywhere.

Listen to the 8-minute and 90-second EarthSky interviews with Chris Field on the IPCC report linking weather extremes to climate change, at the top of the page.

On April 6, 2012 the U.S. Fish and Wildlife Service announced seven grant awards totaling approximately $1.4 million to continue the investigation of white-nose syndrome (WNS) in bats, and to identify ways to manage it. Bats play a critical role in the ecosystems that they inhabit, including farmer’s fields, giving them a key place in agriculture and the U.S. economy. White-nose syndrome has killed more than 5.5 million bats in eastern North America and has spread rapidly across the United States and into Canada since it was first detected in 2006. The disease is named for a white fungus that appears on the bat’s nose and wings.

Jeremy Coleman coordinates efforts to combat white-nose syndrome in bats for the National Fish and Wildlife Service

Jeremy Coleman is national NWS coordinator for the U.S. Fish and Wildlife Service. In the interview below, originally recorded in October 2010, he said the fungus thrives in the cold and damp of caves and mines. He said:

This particular fungus appears to affect bats when they are hibernating, in the winter time.

That’s trouble, come spring and summer, because bats are a natural pesticide for crops. A bat eats its own body weight in insects. Dr. Coleman said White nose syndrome is spread primarily from bat to bat, but he and other scientists suspect that people visiting a cave might carry it on their shoes or gear to other caves. Coleman said:

We don’t have much in our toolkit at this point, to manage the disease, other than trying to slow the spread of it through human movements.

White-nose syndrome in bats spreads as far south as Alabama

Caves across the U.S. are being closed in hopes of protecting hibernating bats. Under consideration, Coleman said, is treating bats with an anti-fungal – like an athlete’s foot medication. He also said:

This is probably not a long term fix because anti fungal compounds are particularly nasty, and have potential side effects for other species

One of the most heavily hit bat species is called the little brown bat, which might be lost to the Northeast U.S. in as few as 15 years. He added:

The species itself is not necessarily going to be extinct because it will be in other parts of – in this case – North America. But in the parts affected by white-nose syndrome, the species will be gone. There may be very small remnant population that will be around for the short term, but it will not be a large enough population to sustain the species over the long term. Functionally, it will be extinct.

Coleman said that the type of drug scientists have spoken about is an anti-fungal drug – the kind of drug we would use for athlete’s foot.

Coleman added that the most important element of saving the bat species into the future is conserving a population large enough to breed and eventually recover their numbers. He’s concerned that treating bats in a lab – where the cave’s environment wouldn’t be affected – might not be worth it. Coleman said:

Anything that could be planned or done with an anti-fungal compound, we would have to be able to do it on a large enough scale that we would be sustaining the population, not just individual bats.

White-nose syndrome originated in New York State in 2006, and it has been spotted as far away as Missouri and Oklahoma. Coleman’s agency is working with other agencies and organizations concerned about bats to create a national response to the disease.

Bottom line: The U.S. Fish and Wildlife Service announced on April 6, 2012 that it had awarded seven grant awards totaling approximately $1.4 million to continue the investigation of white-nose syndrome (WNS) in bats, and to identify ways to manage it. White-nose syndrome has killed more than 5.5 million bats across North America since 2006.

The ancient Maya of Central America and Southern Mexico are famous for developing grand monuments, advanced mathematics, accurate astronomy and beautiful writing. They are also famous for perfecting a calendar to which many attribute predictions that the world will end on December 21, 2012.

EarthSky spoke with Professor David Stuart, an archaeologist and expert on the ancient Maya at the University of Texas at Austin. He told us that neither the Maya, nor their calendar, ever predicted the end of the world.

Magnetic pole reversal not a sign of doomsday

The ancient Maya’s calendar system was developed 1200 years ago. But instead of using just one, they devised a series of calendars to help order the passing of time. These are the Tzolk’in, which measures cycles of 260 days; the Haab, which measures cycles of 365 days; and the Long Count Calendar, which measures cycles of 400 years. Each calendar was used to track different things, such as agricultural, political and cultural events.

Image Credit: roger_jen

On December 21st of this year, the Long Count Calendar will finish a cycle. Many predict that when this cycle ends, so too will our world. But Dr. Stuart said:

There is a date this year – in the year 2012 – in late December, which will see the turn of a cycle. And this is a cycle we call a bak’tun, and a bak’tun occurs every 400 years. So it’s a significant point in the ancient Maya calendar. Now, did the Maya ever say anything about this date? Did they ever predict anything? No – absolutely not.

So where did all this commotion linking 2012 to the end of days actually come from?

Scholars point to “Estela numero seis,” también llamada “Estela de Tortuguero”, an ancient Mayan carving from modern-day Tabasco, Mexico, as the source of the 2012 doomsday myths. This is the only inscription where the ancient Maya mentioned the year 2012. So, we asked Professor Stuart, what does the carving say?

It doesn’t say much. It cites the date but there’s no real prophecy with it. The ancient records actually talk about dates in the future well beyond 2012.

For example, the Temple of the Inscriptions at Palenque, discusses events slated to occur in the year 4772 A.D., far in the future. Stuart said:

The Maya calendar not only doesn’t end, but it keeps going for eons and eons beyond 2012. If you look at the real structure of the calendar it’s almost endless. It goes well beyond the end of our universe and our own kind of scientific cosmology.

Bottom line: Professor David Stuart, an archaeologist and expert on the ancient Maya, told EarthSky that neither the Maya, nor their calendar, ever predicted the end of the world.

Ocean acidification is a change in ocean pH (acid-alkali proportion) caused by increased emissions of CO2 (carbon dioxide) in our modern world. Marine ecologist Joan Kleypas of the National Center for Atmospheric Research will received a prestigious Heinz Award in 2011 for her work on this subject. She published a groundbreaking paper on ocean acidification in the journal Science in 1999, alerting both policymakers and scientists to the issue. Kleypas now works mainly to combat – and help prevent – the effects of ocean acidification on coral reefs. She told EarthSky:

Image Credit: NASA

People wrote me after this paper was published and said you’re wrong, I know you’re wrong – and I’m going to prove you’re wrong. And I actually took comfort in that. But the rebuttals never came. As people looked closely at the pieces of evidence and they looked at the chemistry, they slowly came on board to realize that this is a serious issue.

Dr. Kleypas told us that excess CO2 from the atmosphere makes the oceans more acid – and reduces the amount of carbonate available for some ocean creatures to form their shells. She said:

When we think about a lot of marine organisms – things like corals, clams, oysters, things like hard shells, those shells are made of calcium carbonate. If you reduce the amount of carbonate in the ocean, you reduce the ability of the organisms to secrete their shells.

We often refer to it as being similar to osteoporosis. There are just fewer of the building blocks to build those shells.

Image Credit: NOAA

Kleypas’ focus is on coral reef preservation. She said many corals can’t build up as fast as Earth’s increasingly acidic oceans are breaking them down. Her work involves such things as whether marine algae can remove carbon dioxide from local waters at reef sites. She’s also using computer modeling to figure out which reefs are most likely to benefit from the setup of marine protection zones – because a healthy, undisturbed balance of organisms makes the corals more likely to survive global changes. She told EarthSky:

Most of the work I do is sort of modeling changes at the local scale and at the global scale. One of the big issues with coral reefs in climate change is … how much carbon dioxide is too much carbon dioxide for reef building? A reef is there because it produces more carbon than is removed. It’s amazing, if you ever visit a reef, you’ll see many things are chewing on the reef and breaking it down. Corals have to work hard to build that reef. You can see a balance. If they can’t produce as much calcium carbonate, then at some point these corals may be there but they’re not building a reef any longer.

In some cases, where there are marine algae growing in the reefs, those algae actually absorb carbon dioxide from the water, which can reduce the effects of ocean acidification, at least at the local level.

She said the idea of introducing corals that have been genetically modified to survive high acidity is also on the table. And she explained part of her work involves helping scientists figure out thresholds or “tipping points” for coral reef degradation.

Understanding what the thresholds are is very important because our policymakers are interested in just how high CO2 concentrations can get in the atmosphere. So our information about ecosystem function – it really gives them a guideline of creating future standards of carbon dioxide emissions.

Kleypas said she’s optimistic about her line of research

I like to call these nature’s masterpiece. If we lose coral reefs we’re really losing something that nature took millions of years to produce …

Image Credit: Jim Maragos/U.S. Fish & Wildlife Service