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Bringing Research to Light

February 18, 2011

The Research Staff of the North Carolina Museum of Natural Sciences includes experts in a wide variety of scientific disciplines who conduct exciting research investigations, maintain and expand the Museum’s natural science Research Collections, and participate in the Museum’s public education and outreach mission.  Check this blog often to learn about all of the great science happening at the Museum!

The Sun: Space Weather Machine

June 16, 2015

As temperatures creep toward the triple digits this week,  it’s probably not hard to remember that the Sun is our primary source for heat and light. Perhaps less obvious is that the Sun is also responsible for space weather, defined as the varying conditions surrounding the Earth that are due to solar wind and other energetic outbursts from the Sun’s surface. While there is no conclusive linkage between space weather and Earth’s climate, solar particles penetrating Earth’s magnetic field risk disrupting performance and reliability of space-borne and ground-based technological systems, satellites, and even possibly endangering life. One of the main objectives of space missions currently studying the Sun is to better understand extreme space weather events, how and when they occur, and how life on Earth may be affected, now and in the future.

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Graphic of some of key space weather effects on Earth’s satellites and power grid (Credit: NASA).

STEREO (Solar Terrestrial Relations Observatory) has revolutionized the study of the Sun-Earth system. Consisting of two nearly identical observatories, one ahead and one behind Earth in its orbit of the Sun, STEREO traces the flow of energy and matter from the Sun to the Earth, revealing 3-dimensional structures of violent eruptions coming off the Sun’s surface. If directed toward Earth, these eruptions, called coronal mass ejections (or CMEs), can trigger severe magnetic storms when they collide with Earth’s magnetic field, disrupting satellites and power grids. CMEs are also extremely hazardous to astronauts on the International Space Station and performing Extra Vehicular Activities. Studying these violent solar storms in detail helps scientists understand their fundamental nature and origin, and the extent to which they can affect life on Earth.

STEREO image captured on July 23, 2012, shows a coronal mass ejection that left the sun at the unusually fast speeds of over 1,800 miles per second (Credit: NASA/STEREO).

STEREO image captured on July 23, 2012, shows a coronal mass ejection that left the sun at the unusually fast speeds of over 1,800 miles per second (Credit: NASA/STEREO).

Computer models of superstorms such as the one of 2012, shown above, have helped scientists better understand and predict the onset of storms that could be directed at Earth. By matching their models to past observations, solar astronomers have found that it is not only the origin of CMEs at the Sun’s surface, but also the interactions between successive CMEs farther out in interplanetary space that contribute to extreme space weather events. The Solar Dynamics Observatory (SDO) is another satellite mission taking unprecedented images of the Sun, showing its surface features, storms and flares in great detail, enabling the study of solar prominences and energetic outbursts that regularly spew into space. Orbiting the Earth at nearly 7000 miles per hour, SDO has captured the most detailed imagery of the Sun to date, revealing its surface in amazing fiery and dynamic detail. The image below shows a dark region called a coronal hole in the surface of the Sun, an area where high-speed solar wind particles stream into space.

Imaged by the Solar Dynamics Observatory, a large, dark coronal hole is shown in dark blue at the bottom of the Sun. Coronal holes are areas where the Sun's magnetic field is open ended and where high-speed solar wind streams into space. At its widest point, the hole extends about half way across of the Sun, close to 50 times the size of Earth. (Credit: Solar Dynamics Observatory, NASA).

Imaged by the Solar Dynamics Observatory, a large, dark coronal hole is shown in dark blue at the bottom of the Sun. Coronal holes are areas where the Sun’s magnetic field is open ended and where high-speed solar wind streams into space. At its widest point, the hole extends about half way across of the Sun, close to 50 times the size of Earth. (Credit: Solar Dynamics Observatory, NASA).

Solar flares are sudden flashes of brightness from the Sun’s surface, linked to great releases of energy, often occurring just prior to CMEs. Such bright regions can be seen in many SDO images, including the one below, which also shows loops of superheated plasma seen extending off the surface; these loops can’t escape the magnetic filed of the Sun but rather follow the field lines back to the surface.

Active regions on the surface of the Sun, showing  cascading loops of superheated plasma following a solar eruption. Each loop is the size of several Earths. The Solar Dynamics Observatory captured this image in Ultraviolet light wavelengths (Credit: Solar Dynamics Observatory).

Active regions on the surface of the Sun, showing cascading loops of superheated plasma following a solar eruption. Each loop is the size of several Earths. The Solar Dynamics Observatory captured this image in ultraviolet light wavelengths (Credit: Solar Dynamics Observatory).

Solar flares strongly influence space weather near Earth, producing streams of energetic particles in the solar wind. When solar wind particles impact the Earth’s magnetic field, they can generate a geomagnetic storm which presents radiation hazards to satellites and humans on Earth and in space. To generate some of the remarkable imagery and videos for scientists and astronomy enthusiasts, SDO’s instruments capture images of the Sun at frequent intervals, showing how the surface changes rapidly. The gorgeous composite below was made from 25 separate images taken at extreme ultraviolet wavelengths, which enable viewing very high temperature solar material.

Composite image spanning the period of April 16, 2012 to April 15, 2013, taken by SDO's Atmospheric Imaging Assembly (AIA), which captures a shot of the sun every 12 seconds in 10 different wavelengths. At extreme ultraviolet wavelengths, solar material is at a steamy 600,000 degrees Kelvin (more than 1 million degrees Fahrenheit) [Credit: NASA's Goddard Space Flight Center/SDO/S. Wiessinger].

Composite image spanning the period of April 16, 2012 to April 15, 2013, taken by SDO’s Atmospheric Imaging Assembly (AIA), which captures a shot of the sun every 12 seconds in 10 different wavelengths. At extreme ultraviolet wavelengths, solar material is at a steamy 600,000 degrees Kelvin (more than 1 million degrees Fahrenheit) [Credit: NASA’s Goddard Space Flight Center/SDO/S. Wiessinger].

You can see the Sun changing over the course of 3 years in this video. Because the distance between the SDO spacecraft and the Sun varies over time, the apparent size of the Sun subtly increases and decreases over time in the video. What does extreme space weather mean for our future? Aside from immediate power grid and satellite concerns, short-term radiation risks posed by solar flares are being considering in current planning stages for sending humans to Mars, the Moon, and even other planets. Energetic protons passing through the human body can cause serious biochemical damage, harming astronauts not only during interplanetary travel but also once they arrive at their destination. In the very far future, the Sun will become a red giant and engulf the Earth; but not to worry, as this won’t happen for another 5 billion years or so. In the meantime, scientists are studying space weather and extreme solar events that can affect life on our planet in order to be better prepared for living with our star. This information is further useful for understanding how stars affect life on planets beyond our solar system, some of which may ultimately be the future home for our species long after the Sun is gone. For more amazing solar footage, play the video compilation of SDO’s “best video imagery” from the last 5 years, below:

Want to learn more about the Sun, extreme space weather, and solar missions, and view its surface safely through solar telescopes? Join us for International SUNday (and the first day of summer!) this Sunday, June 21, for special presentations and solar viewing (weather permitting). More details on International SUNday can be found here.

The Little Robot That Could

June 14, 2015

The little space-bot, Philae, made history last November by being the first-ever robot to land on a comet. While amazing in its technological feats and detailed measurements of comet 67P taken at close range, all was not perfect with this historic landing, leading European Space Agency (ESA) scientists to admit that, shortly after landing they did not in fact know Philae’s location on the comet.

The glitch was a misfire of Philae’s landing harpoons such that the robot bounced off the comet twice, eventually becoming wedged in one of the comet’s cliffs, the precise location of which, the scientists admitted, was unknown.

Panoramic image of Philae's final landing site captured by the Rosetta orbiter's CIVA-P imaging system.  The 360º view shows roughly the point of final touchdown. The lander is sketched on top of the image in its estimated configuration (Credit: ESA/Rosetta/Philae/CIVA).

Panoramic image of Philae’s final landing site captured by the Rosetta orbiter’s CIVA-P imaging system.
The 360º view shows roughly the point of final touchdown. The lander is sketched on top of the image in its estimated configuration (Credit: ESA/Rosetta/Philae/CIVA).

Due to the non-sticky landing, the final orientation of Philae’s solar panels were such that it was unable to capture enough sunlight to power its instruments. Yet, not to be undone, mission scientists completed nearly all of the robot’s science goals atop the comet within the 60 hours of the lander’s battery life. Further, through the brief contact window, mission engineers were able to rotate the Philae’s solar panels in such a way that, just possibly, Philae might capture enough sunlight to “reawaken” and continue its groundbreaking science as comet 67P neared the inner solar system, thought to be sometime during the summer of 2015.

Now, Philae has made history again. To great excitement, the little robot has awakened from its long hibernation, with the news revealed via ESA mission Tweet:

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Rosetta mission scientists today stated that Philae is doing quite well, communicating with the ground team for 85 seconds. With an operating temperature of -35ºC (-31ºF), it has acquired enough sunlight to power operations so that it may continue exploring the cometary molecules that are the primitive leftovers from solar system formation. Studying these molecules will give scientists clues as to how our solar system, and possibly life, formed and evolved.

Rosetta scientists analyzing the new data think that Philae may actually have been awake even earlier than today. They now await next contact so that the 8000 data packets in the robot’s memory can be analyzed, hopefully revealing clues as to what new information Philae gathered in the past few days of mysterious operations.

Fans of this mission may recall Professor Monica Grady’s sheer joy on landing day, November 12, 2014, a reminder of the true passion scientists have for their work:

If you think that reaction was atypical, Dr. Grady revealed today that, upon hearing Philae’s news while in a taxi, she was so excited she hugged the driver. Congratulations, Philae, your team, and all who root for you!

iJupiter

February 8, 2015

Jupiter: giant planetary overlord of our solar system. From Earth, Jupiter’s gargantuan presence is hardly evident on a daily basis; to us it is a far-away dot in the night sky (albeit the third-brightest after the Moon and Venus).

But, Jupiter is special and significant. With a mass equal to 2.5 times that of all the other planets combined, it is by far the largest planet in the solar system. Light from Jupiter can be bright enough to cast shadows on Earth, which is impressive given that its average distance from us hovers between ~ 460 million and 510 million miles. And, while it is the great giant of our planets, Jupiter is made up primarily of the lightest of gases: hydrogen (primarily) and helium. While it may have a rocky core, it has no solid surface to speak of, rendering it most difficult to imagine as either a haven for extraterrestrial life, or a destination for futuristic human space travelers.

Montage of Jupiter and the Galilean satellites, taken by the Galileo spacecraft [satellites, top to bottom: Io, Europa, Ganymede, Callisto]. The Great Red Spot on Jupiter's surface is a persistent storm that is larger than Earth (Credit: NASA/JPL/DLR).

Montage of Jupiter and the Galilean satellites, taken by the Galileo spacecraft [satellites, top to bottom: Io, Europa, Ganymede, Callisto]. The Great Red Spot on Jupiter’s surface is a persistent storm that is larger than Earth (Credit: NASA/JPL/DLR).

Due to its large mass and consequently strong gravitational pull, Jupiter acts as a “cosmic vacuum cleaner,” protecting Earth from being pelted with many more asteroids and comets than have reached the surface throughout its history.  The impact rate on Jupiter has been estimated to be between two- and eight- thousand times greater than Earth, and without Jupiter it is hypothesized that life on Earth may not have made it this far. In fact, scientists think that habitability on any Earth-like planet — in exoplanetary systems in the Galaxy — may in part depend on a nearby Jupiter-like giant that attracts a large percentage of space debris.

As recently as the 1990s, Jupiter has shown it can do the job. In 1992, astronomers witnessed the break up of comet Shoemaker-Levy 9, torn apart by Jupiter’s gravitational forces, leading to it being described as a “string of pearls”:

A NASA Hubble Space Telescope (HST) image of comet Shoemaker-Levy 9, taken on May 17, 1994, with the Wide Field Planetary Camera 2 (WFPC2) in wide field mode. When the comet was observed, its train of 21 icy fragments stretched across 1.1 million km (710 thousand miles) of space, or 3 times the distance between Earth and the Moon (Image Credit: NASA/ESA and H. Weaver and E. Smith (STScI)).

A NASA Hubble Space Telescope image of comet Shoemaker-Levy 9, taken on May 17, 1994. When the comet was observed, its train of 21 icy fragments stretched across 710 thousand miles of space, or 3 times the distance between Earth and the Moon (Image Credit: NASA/ESA and H. Weaver and E. Smith [STScI]).

In 1994, the comet’s 21 discernible fragments, with diameters up to 2 km (~ 1.2 miles), collided with Jupiter at speeds exceeding 130,000 miles per hour. If even one of those fragments had reached a populated region of Earth, the result would likely have been more than just a cosmic light show.

Comet Shoemaker-Levy 9 collision with Jupiter (Credit: NASA).

Comet Shoemaker-Levy 9 collision with Jupiter (Credit: NASA).

In addition to their physical grandeur, Jupiter and its four most prominent moons — Io, Europa, Io, Ganymede, and Callisto (see the image montage, above) — figure prominently in the evolution of our understanding of the solar system. Now aptly referred to as the “Galilean Satellites”, these four moons were discovered by Galileo Galilei in 1610, marking one of the most significant contributions to science. Galileo used a homemade telescope to make these observations which helped him prove that, without doubt, the Sun, not the Earth (as thought at the time), was the center of the solar system.

A translation of the key passages of Galileo Galilei's journal detailing his discovery of four moons orbiting Jupiter in January, 1610. The moons, later named Io, Europa, Callisto and Ganymede, were the first discovered beyond Earth (Image Credit: NASA).

A translation of the key passages of Galileo Galilei’s journal detailing his discovery of four moons orbiting Jupiter in January, 1610. The moons, later named Io, Europa, Callisto and Ganymede, were the first discovered beyond Earth (Image Credit: NASA).

Galileo Galilei is often referred to as “the father of modern observational astronomy” for his work on the Jupiter system, the phases of Venus, and sunspots, and he laid the foundation for today’s modern space probes and telescopes. In the more than 400 years since, we’ve certainly come a long way technologically. Data and images from the Voyager and Galileo missions to Jupiter and the outer planets have revealed incredible details of these foreign worlds. The year 2012 marked the 35th Anniversary of Voyager, now in interstellar space, making it the farthest spacecraft ever launched from Earth.

Close-up view of Jupiter's Giant Red Spot, taken by the Voyager spacecraft (Image Credit: NASA).

Close-up view of Jupiter’s Giant Red Spot, taken by the Voyager spacecraft (Image Credit: NASA).

While our record of state-of-the-art space exploration is, rightfully, marked by missions backed by multinational consortia of space agencies and years of development, it should also be remembered developments in technology now give us hand-held devices that can help put astronomy at your fingertips.

I was recently involved in a public observing night, led by my colleague Professor Daniel Caton, at Appalachian State University’s Dark Sky Observatory in the mountains of Boone. It was a wonderfully clear night, during which we got a wonderful glimpse of the Geminid meteor shower. At one point, Jupiter and its four sparkling moons were put into view through the Observatory’s excellent 32-inch telescope. After the crowd dispersed I took a few minutes to fiddle with aligning my iPhone just so, and captured the image below:

Jupiter and the Galilean Moons, taken with my iPhone through the 32-inch telescope at Dark Sky Observatory (Image credit: R. Smith)

Jupiter and the Galilean Moons, taken with my iPhone through the 32-inch telescope at Dark Sky Observatory. Moons from left to right: Io, Callisto, Ganymede, Europa (Image credit: R. Smith)

I’ll stay tuned for a device one can whip out to capture 200x magnification of the celestial object of their choice — an “iTelescope”, if you will. For now, I like knowing that it’s not that hard to take a pretty decent image of a far-away system through the eyepiece of a moderately sized telescope, just with an iPhone. And now I have Jupiter in my pocket.

Part II- Ten New Diamonds from NC

December 9, 2014
This octahedral diamond cyrstal looks like it has been faceted. These are all growth textures on the triangular crystal faces. Also, this is my favorite picture.

This octahedral diamond cyrstal looks like it has been faceted. These are all growth textures on the triangular crystal faces. Also, this is my favorite picture.

One of the comments on the earlier blog post came from Richard Jacquot:

rick@wncrocks.com commented …In an article published with Ed Speer in Volume 1, Issue 2 of American Rockhound magazine in June, 2014, we discussed 15 diamonds that were found in Reedy Creek in Mecklenburg County. These diamonds were found by a gold prospector and sold to a reputable local mineral dealer. They were then sold to various collectors. This was around 1999. The diamonds averaged .5 carat and 1-2mm. The diamonds have been tested and there is no reason not to believe that the prospector found these, in fact, the story is very similar to this one. So what is the criteria for getting them authenticated?

To bring everyone else up to speed, Richard is publisher, editor, and in this case, also a writer for American Rockhound magazine. American Rockhound is a new addition to the world of magazines, so the distribution is not yet large, but I wish him and his co-authors much success. Goodness grows in North Carolina, and that includes the minerals.

As with any scientific question, the question finally revolves around who has the data, and what data do we (I) have in hand? I wasn’t able to get hold of a copy of the article, so I can’t speak to any of the particulars of that diamond find and sale. I don’t know any of the people involved, so I can’t really make a meaningful comment on that, either. I don’t have any evidence one way or the other. I do know about this diamond find, so I’ll go with what I know. Here’s how I approach the problem.

“Authenticate” covers a lot of territory. It’s not like these are antiques. I knew with about 95% certainty that these were diamonds from the moment I opened the package. The next step was to collect data to support that identification. Diamonds are isotropic on my petrographic scope- that is, in cross polarized light, they stay dark. Second was to look at the composition: EDS. With the great big carbon peak, there wasn’t much doubt.

The next question was natural vs. synthetic. For that I needed the assistance of a genuine diamond expert, and Diamonds Direct Crabtree came to the rescue.  The verdict from the Gemological Institute of America was that the diamonds are natural.

The final step is like any other scientific study: reproduction of results. Could we reproduce Jeff’s findings, and then find the source of the diamonds? We were still working at that when Jeff died.

Rockhounds in the field tend to be very focused on what they want. I’m not a rockhound, I’m a research scientist. Rockhounds and other amateur geologists tend to be surprised at what I want, which is everything. A prospector may find gold in quartz veins, but then he’s surprised that I want the quartz, and the sulfide minerals. These minerals contain oxygen, hydrogen and sulfur isotopes that illuminate the origins of the gold-bearing fluid. Size is not an issue for analysis. The quartz usually contains fluid inclusions, fossil water that can be used to determine the temperature at which the veins formed. I want to know the relationships between the minerals and the gold, who’s first, who’s second, etc. Minerals are information to me.

Anyone discovering diamonds has a choice about what to do with that information. Do they withhold it, so they have monopoly on the sources? Good business sense, but not good scientific sense. Jeff shared data, and we got started on finding the source rocks. The burden of proof that these were North Carolina diamonds was clearly on him, and he was cooperative and helpful in working on the problem. I analyzed the other minerals that were panned with the diamonds, using the petrographic microscope and the SEM/EDS. We made thin sections of possible candidates for the source rock.  I was confident enough to make the recent announcement, but prudent enough to keep working on the problem. A quick check of my birth certificate shows that I wasn’t born yesterday.

I don’t think so much about “authentication” as much as I do about “reproducing results.” Science is a good discipline for separating out what you know, what you can surmise, and what you don’t know, and for building multiple working hypotheses to test along the way. I have the diamonds, I have some of the minerals from the streams. I have several working hypotheses about source rocks to target.

I can understand skepticism about the discovery of the diamonds. Even if we had TV cameras on Jeff as he found them, there would still be suspicion about the sediments being salted, or even that the diamonds were purchased somewhere else. If we can reproduce Jeff’s results that would be strong support that these diamonds are from North Carolina. Finding the source would certainly clinch the question.

Astute readers will notice that I have been very vague about location of this discovery. True. I have a responsibility as an employee of the state of North Carolina to preserve a good relationship with land owners. Field guides to collecting minerals or fossils in North Carolina tend to result sites being destroyed or placed off limits to collection. Most collectors in the state are very careful and responsible, but it only takes one bad one to ruin things for everybody.

Early next year, we will be crowdfunding the costs of the research. The work has several lines of inquiry: (1) identification of the inclusions in the diamonds; (2) field work to obtain more samples of heavy minerals from the streams; and (3) microanalysis of mineral separates taken from the streams.

Stay tuned. Next blog up, multiple working hypotheses and geological research.

Ten New North Carolina Diamonds

December 4, 2014
This octahedral diamond cyrstal looks like it has been faceted. These are all growth textures on the triangular crystal faces.

NCSM 5997. This octahedral diamond crystal looks like it has been faceted. These are all natural growth textures on the triangular crystal faces.

There have been 13 diamonds found in the state of North Carolina since 1893, the largest of which was four carats. Most of them were found as a result of panning operations for gold or monazite. One of these is in the Geology Collection of the Museum of Natural Sciences: NCSM 3225. It came from Burke County and was part of the collection of J.A.D. Stephenson, the man who discovered emeralds and chromian spodumene (aka hiddenite) in Alexander County.

NCSM 3225, one of the original thirteeen diamonds found in North Carolina. From the collection of J.A.D Stephenson.

NCSM 3225, one of the original thirteeen diamonds found in North Carolina. From the collection of J.A.D Stephenson.

You can imagine my feelings when 13 more diamonds came into my laboratory, all at one time.

In many ways this story belongs to Jeff Moyer of Mount Pleasant, North Carolina, a gold prospector and amateur exploration geologist. Jeff was the most gifted amateur geologist I ever met. He was a keen student of history, consulting records from the old Charlotte Mint and taking time to learn the oral history of the areas where he worked. He designed and patented his own equipment. Our conversations about North Carolina geology were long and detailed, like I was having a thesis defense all over again. His restless and curious intellect eventually became fascinated with the idea of finding the source of North Carolina’s diamonds. So he modified his equipment to trap diamonds as well as gold. And it worked.

I have met all sorts of miners over the years, and Jeff impressed me as genuine. We purchased 10 of the diamonds, and I went to work. Jeff and I made plans to go into the field to reproduce his findings. It never happened. Jeff was diagnosed with Stage 4 lung cancer, and died shortly thereafter.

My instinct was that Jeff was honest, and not trying to put anything over on me and the Museum. But there is always the nagging suspicion that diamonds could be synthetic and not natural. Perhaps someone was salting Jeff’s area as a joke. We needed independent verification of the diamonds. I did everything I could. EDS analysis on the scanning electron microprobe at the Analytical Instrumentation Facility at NC State showed that they were diamonds with traces of iron, silicon and aluminum on the surface, consistent with a natural origin. The diamonds were also a variety of crystal shapes. Synthetic stones tend to be all of one crystal shape.

My own scientific expertise is in mineralogy, particularly thermodynamics and microanalysis. Minerals tell the entire story of the rock, but in this case, I couldn’t read it. The processes of making synthetic diamonds can be shrouded in secrecy, and the engineering moves faster than I can keep track of it. I needed an expert in diamonds, someone conversant in the ways to tell synthetic stones from natural stones. And there the project sat for many years. The Museum did not have the money to send the samples out for independent evaluation.

Fortunately for me, our new Director, Emlyn Koster, took an interest in the project. His commute every day took him past Diamonds Direct Crabtree, a North Carolina based diamond firm. They were diamond experts, why don’t we approach them?  <Facepalm> Why didn’t I think of that?

The Vice President of Diamonds Direct Crabtree, Mr. Barak Henis, took a personal interest in the diamonds. Diamonds Direct has an ongoing relationship with the Gemological Institute of America, so they sponsored the Museum by sending five of the diamonds for evaluation. They saved us a great deal of money.

The verdict came back: the stones were natural diamond. The people at Diamonds Direct Crabtree were as excited as we were.

So, dear readers, the Museum of Natural Sciences, Diamonds Direct Crabtree, and I are pleased to announce the discovery of 10 new diamonds from North Carolina.  This is exciting news for everyone. These diamonds are small, but it means we are one step closer to finding the source of diamonds in North Carolina. It also means that there is a scientific treasure trove waiting to tell us about the mantle far below North Carolina. I’ll take a look at that in later blog posts.

It also means we are one step closer to fulfilling Jeff Moyer’s legacy. Rest in peace, Jeff. You were right.

All ten new NC diamonds, on a millimeter grid for scale.

All ten new NC diamonds, on a millimeter grid for scale.

Pictures shown below were taken with the new Keyance Digital Microscope, purchased for Research and Collections thanks to a bequest from the estate of Renaldo Kuhler.  

NCSM5994.

NCSM5994.

NCSM 5995.

NCSM 5995.

NCSM 5996, a dodecahedral diamond crystal.

NCSM 5996, a dodecahedral diamond crystal.

NCSM 5997, a modified octahedron.

NCSM 5997, a modified octahedron.

NCSM 5998

NCSM 5998.

NCSM 5999. This is a perfect octahedron,

NCSM 5999. This is a perfect octahedron.

NCSM 6000.

NCSM 6000.

NCSM 6001.

NCSM 6001.

NCSM 6002.

NCSM 6002.

NCSM 6003.

NCSM 6003.

Conserving Asian newts could save the world’s salamanders

December 3, 2014

By Dr. Jodi Rowley, Dr. Bryan Stuart

Hong Kong Newt (Paramesotriton hongkongensis), Hong Kong. Copyright Dr. Jodi J L Rowley.

Hong Kong Newt (Paramesotriton hongkongensis), Hong Kong. Copyright Jodi J L Rowley.

Salamanders are popular as pets in many countries. To satisfy this demand, they are harvested from the wild and transported across the planet. But moving animals around the world also moves their parasites and pathogens. Recently, a newly discovered species of chytrid fungus appears to have hitchhiked to Europe on the skin of imported pet Asian salamanders of the family Salamandridae (‘newts’). Researchers have determined that Asian newts have co-existed with this fungus for perhaps 30 million years, and during that time evolved some protection from it. Unfortunately, laboratory experiments have shown that the fungus can be deadly to salamanders that have never been exposed to it, elsewhere in the world (more).

Scientists have rightly recommended that the international trade of live salamanders be more tightly controlled to prevent the spread of this fungal pathogen into European and North American salamander populations. But the plight of the Asian newts, which are threatened by overharvesting for the same pet trade, has received little attention. Controlling the global trade of live salamanders is vital to ensuring the survival of the Asian newts, too.

The tailed amphibians, or salamanders, are beautiful and usually gentle creatures, so it’s not surprising that people enjoy keeping them in terraria and aquaria as pets. However, to supply the pet trade, wild salamanders are collected from around the world, especially the rainforests of Central America and the cool, mountain streams of Asia.

A recent paper reported that a newly discovered amphibian chytrid fungus Batrachochytrium salamandrivorans (Bs) likely originated in Asia and hitchhiked to Europe on the skin of wild Asian newts imported to supply the pet trade.

The paper raised alarm that Bs now poses a threat to wild populations of European and North American salamanders. Already wild salamander populations in Europe appear to be declining. While this paper rightly sparked global alarm for the future of European and North American salamanders, the conservation crisis facing Asian newts themselves has not received enough attention.

More than one-third of all species of Southeast and East Asian newts are at risk of extinction, many due to overharvesting for the international pet trade. The Lao Newt (Laotriton laoensis) is an unusual, colorful species that lives only in a small part of northern Laos, and outside of any the country’s protected areas (more).

Shortly after the species was discovered and described to science in 2002, commercial collectors from Germany and Japan visited villages in Laos to obtain these rare newts for sale into the pet trade back at home (more). The government of Laos has since passed legislation banning the commercial trade of the newts in Laos, but unfortunately, illegal trade continues today. Many of the people who live near the Lao Newt are poor and unable to resist the money offered to them by illegal collectors, who then re-sell the newts to pet markets in Europe, Japan and the United States. Sadly, the Lao Newt is now Endangered in the wild, primarily due to illegal harvesting for the international pet trade.

Despite their protection in Laos, little can be done to stop the transportation and sale of Lao Newts once they leave the country, destined for the pet trade abroad. For example, no Asian newt species are currently listed in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), an international agreement that is intended to protect certain species from overexploitation.

The discovery of the origin of Bs presents a renewed opportunity to curb the sale of live Asian newts around the world. Lao Newts have not yet been tested for Bs, but the fungus has been in three other, very closely related species of Asian newts, and the Lao Newt probably carries it. Controlling the trade of live Asian newts will prevent European and North American salamanders from being further exposed to this fungal pathogen- and will also keep Asian newts safe in the wild.

Fortunately, some countries, including Australia, do not allow importing salamanders as pets. Other countries should follow suit to protect wild salamanders. In the meantime, many Asian newt species should be listed in the CITES convention. And countries around the world need to control the importation of live Asian newts as seriously as they do live poultry and livestock that also pose disease risks to domestic populations. Western and Asian countries should work together to curb the trade of live Asian newts. Doing so will keep Asian newts in the wild and the Western salamanders fungus-free. Otherwise, a global catastrophe to our world’s salamanders awaits.

Dr Jodi Rowley
Australian Museum Research Institute

Dr Bryan Stuart
North Carolina Museum of Natural Sciences

More information:
Stuart, B. L., Rowley, J.J.L., Phimmachak, S., Aowphol, A. & Sivongxay, N. (2014). Salamander protection starts with the newt.Science 346 (6213): 1067-1068.

Mars, Rainbow Planet

November 22, 2014

In fact, Mars is still our solar system’s beloved “Red Planet”, so-named for the abundance of iron oxide on its surface. And if held in your hand, Mars rocks most Mars rocks will appear rather similar to rocks from our home planet. However, also like rocks from Earth and other planetary bodies, very thin slices, or thin sections, of Martian terrain will look brilliantly colored using polarized light microscopy, a method that depends on how light bends through materials with varying optical properties, and used in identifying crystals and minerals .

We recently started imaging a new set of Martian and other extraterrestrial samples in the Astronomy & Astrophysics Research Lab, beginning with Martian rocks, shown below in brilliant color.

But first, how can we have samples of Mars, since we’ve never had a mission return with any rocks? The answer: meteorites. Out of more than 61,000 meteorites found on Earth, 132 are thought to be from Mars. Their origin is deduced primarily from their unique relative composition of trapped gases (Mars’ atmosphere is nearly 96% carbon dioxide, with nearly 2% each argon and nitrogen, and less than 1% oxygen and carbon monoxide), which we know to great accuracy from our missions to Mars. Some time in the past, these future meteorites were blasted off the surface of Mars from the impact of a large body, most likely an asteroid, then traveled in space for thousands, even millions of years, before reaching Earth.

Compare the two images below. The  first shows the thin section from the Martian meteorite, Tissint, seen with our unaided eye. The second image below shows Tissint in polarized light, revealing the large olivine minerals which are colored due to the way the light bends as it passes through the complex crystalline structures.

Thin section of the Martian meteorite, Tissint, as seen with the unaided eye (Image credit: Anna Morris, Astronomy & Astrophysics Research Lab, NCMNS).

Thin section of the Martian meteorite, Tissint, as seen with the unaided eye (Image credit: Anna Morris, Astronomy & Astrophysics Research Lab, NCMNS).

TissintPano-sm-framed copy

Tissint thin section as seen in polarized light, in the 1/2-wavelength setting. Large olivine crystals are seen as colorful structures in a complex mineral matrix (Image credit: Anna Morris, Astronomy & Astrophysics Research Lab, NCMNS).

The Tissint meteorite is classified as a shergottite, one of the four main subdivisions of meteorites from Mars, and representing nearly 3/4 of all Mars meteorites. Shergottites are igneous, meaning they formed from the cooling and solidification of lava during a time of active volcanism on Mars.  The shergottite group is named after the first of these meteorite types, the Shergotty meteorite, which fell in Sherghati India in 1865. Tissint is an igneous basalt that is rich in the mineral olivine, large inclusions of which are readily evident in thin sections.

Unlike other types of meteorites that are very primitive solar system material, shergottites are most likely younger, with most age estimates ranging from less than one million to several million years old; however, the large degree of processing from magma and impacts make these samples more difficult to age than primitive, pristine samples.  A 2014 (and controversial) paper in the journal Science  suggested that the Mojave crater on Mars could be the source of the shergottite meteorites, and that the samples represent very ancient material — exceeding 4 billion years — that was ejected from the less-than 5 million year-old crater. The precise age of the shergottites remains comsochemistry’s key unanswered questions.

Terrain model of Mojave Crater on Mars, generated from a stereo pair of images provides this synthesized, oblique view of a portion of the wall terraces of Mojave Crater in the Xanthe Terra region of Mars. The model yielding this view combines data from a pair of images taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter (Image credit: NASA/JPL-Caltech/University of Arizona).

Terrain model of Mojave Crater on Mars, generated from a stereo pair of images provides this synthesized, oblique view of a portion of the wall terraces of Mojave Crater in the Xanthe Terra region of Mars. The model yielding this view combines data from a pair of images taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter (Image credit: NASA/JPL-Caltech/University of Arizona).

A fairly substantial body is thought to have been necessary to hit Mars hard enough to eject material from the surface in order to  escape its gravity, which is about 38% that of Earth’s gravity. The large olivine crystals in Tissint show cracks that are the likely signatures from this impact event. Long black veins are also thought to be the result of shocking the rock, and the matrix (the material surrounding the olivine crystals) contains a glassy material called maskelynite plagioclase that formed during impact.

The images below show close-ups of two different olivine crystals in our sample, and their surrounding matrix. The left, middle, and right columns are 1/4, 1/2 and one-wavelength, which describes the different polarizer settings, each of which reveals various features including black veins of shocked glass in the matrix, and deep cracks in the olivine crystals.

Close-up polarized light image of an olivine crystal in our Tissint thin section. Deep cracks can be seen running through the crystal. Left to right: 1/4, 1/2 and 1-wavelength of light. Top to bottom: 5x, 10x, 20x, 50x zoom (Image credit: Anna Morris, Astronomy & Astrophysics Research Lab, NCMNS).

Close-up polarized light image of an olivine crystal in our Tissint thin section. Deep cracks can be seen running through the crystal. Left to right: 1/4, 1/2 and 1-wavelength of light. Top to bottom: 5x, 10x, 20x, 50x zoom (Image credit: Anna Morris, Astronomy & Astrophysics Research Lab, NCMNS).

Close-up polarized light image of an olivine crystal in our Tissint thin section. Deep cracks can be seen running through the crystal. Left to right: 1/4, 1/2 and 1-wavelength of light. Top to bottom: 5x, 10x, 20x, 50x zoom (Image credit: Anna Morris, Astronomy & Astrophysics Research Lab, NCMNS).

Close-up polarized light image of an olivine crystal in our Tissint thin section. Deep cracks can be seen running through the crystal. Left to right: 1/4, 1/2 and 1-wavelength of light. Top to bottom: 5x, 10x, 20x, 50x zoom (Image credit: Anna Morris, Astronomy & Astrophysics Research Lab, NCMNS).

Tissint was discovered by nomads in the small town of Tissint east of Tata, Morocco, on July 18, 2011. It is the fifth Martian meteorite seen to fall to Earth (as opposed to “finds”, or meteorites that are found some time after falling), and is scientifically more valuable than the former given that samples are less weathered, and the trajectory of the meteor can be studied as well. The sky reportedly shown bright yellow during the fall, and two sonic booms were heard.

Anna Morris, Astronomy & Astrophysics Research Lab volunteer, working at our Nikon Polarizing light microscope. Anna's main project in the Lab is to image our meteorite thin sections at a wide range of magnifications and various polarization settings. The images can then be used for identification and further analysis of the minerals.

Anna Morris, Astronomy & Astrophysics Research Lab volunteer, working at our Nikon Polarizing light microscope. Anna’s main project in the Lab is to image our meteorite thin sections at a wide range of magnifications and various polarization settings. The images can then be used for identification and further analysis of the minerals.

We are grateful to Donald Cline, Director and CEO of the Pisgah Astronomical Research Institute, for providing the thin sections to the Museum for our work.

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I am an observational astronomer studying solar system origins from a different vantage point: outside of our solar system. I use the largest ground-based optical/infrared telescopes to study the chemistry of forming planetary systems in our Galaxy, and compare these data to the oldest material from our solar system, including meteorites and the Sun. My astronomical data directly connect to understanding unusual chemistry in the most primitive meteorites, which helps in understanding the earliest processes that influenced how planets formed here, and beyond the solar system. I am interested in expanding our meteorite studies in the Lab. You can visit some key meteorite specimens on display in the meteorite exhibit, adjacent to the Astronomy & Astrophysics Research Lab. Also, visit my Museum webpage and other research blogs if you would like to learn more about my research.

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