To Death Valley or Not to Death Valley

Warning: not amateur science. This one is more like, what I did this weekend for fun.

Recently we made the move from Idaho to Nevada. Part of the tradeoff from the move included the ability to drive from the relatively high elevation cold temperature basin and range country to the lowest spot in the country, Death Valley, within a few hours. As the forecast for this weekend included snow at the new home in Nevada, I thought to take advantage of the nice weather I expected at -200 ft elevation of Standpipe Wells.

The drive from our neck of the woods to Death Valley involves a relatively uneventful trip south through Tonopah and then Beatty Nevada. This is the southern edge of the Nevada basin and range where the topography makes the transition to more subdued alluvial fill basins separating widely spaced mountains. The total elevation drop is something like 6700 feet in a three and a half hour drive. The majority of the drop is in the final thirty miles out of Beatty and down the mountain range into Death Valley. My ears popped the entire way down.

Yawning and chewing gum on the Daylight Pass road into Death Valley, the basin opens up with a wide view of Standpipe Wells to the southwest and Furnace Creek to the south. The mountains to each side are rich in complex structural geology, including on peak to the north that is suffuciently faulted to be called Corkscrew Peak. The road comes over the pass onto a steep alluvial fan, maybe a six percent grade. Large boulders litter the slope at the top of the fan and grades to smaller and smaller rock as you drive toward the valley basin. Occasional monolithic outcrops emerge from the smooth alluvial fan, very out of place blocks rotating out from the faulted basin fringes. The driver slows down to a turtles pace to navigate the road placed in a channel eroded from just such a block called Mud Canyon.

The road makes an unnecessarily complex set of turns that allows you to head north to Scotty's castle, south to Furnace creek or continue west to Stovepipe Wells.

Stovepipe Wells is a little outpost composed of a motel, gas station, campground and ranger station. The last time we visited, we stayed the night at the motel. As with any national park hotel it was insanely overpriced and provide an adequate living space. In late October, when the rest of the country is facing the pre-Halloween blizzard, Stovepipe Wells is the perfect temperature. There is little better than waking up at seven am to find the sun edging over the surrounding mountains casting the entire valley in the soft glow of the dawn magic hour.

Right down the road there is a dirt road forging up the alluvial fan to the south toward the base of the towering Tucki Mountain. The gravel parking lot at the top of the road is at the outlet of Mosaic Canyon. When I visited there was blue skies with a hint of black storm cloud sending feelers over the top of the mountain and a whole parking lot full of cars. Now Mosaic Canyon is one of those amazing little features that funnels an entire mountain range's worth of runoff through a two foot wide and twenty foot deep canyon...maybe once or twice a year when the rain comes. My concern at the time was that the rain clouds that were ominously rumbling up at the peak of the mountain were preparing to send a wave of water, trees, rocks and tourists down the trail at me.

The geology of the canyon was great. The reason folks go to Mosaic Canyon is because of the butter smooth marble walls of the lower canyon. The marble is truly beautiful with alternating bands of orange, cream, and dark brown - if it weren't in a national park, they would be making counters from the stuff. The periodic water and gravel abrasions scalloped and ground the marble to the point where it became "soft" as a youngster exclaimed as he slid down one of the walls. The good stuff was all within a quarter mile of the parking lot.

The marble is not the only interesting geology. There was a fine grained matrix supported coarse, angular clast conglomerate that could be found at the upper contact of the marble, although it could also have been lithified alluvium or possibly volcanoclastic. Large pumice boulders were occasionally sticking out of the canyon wall above the marble. Higher up the canyon mineralized ironstones and quartz laden metasedimentary rocks litterered the canyon floor. The slopes lining the canyon walls were red metasedimentary rocks and looked mineralized but I did not see evidence of mining. The canyon became unaccessible about a mile up from the parking lot at a steep cliff that would have been a challenge to free climb.

 

The next destination was to find a camp site and maybe check out some of the old mining that happened at Death Valley. Continuing on the road going west from Standpipe Wells, the highway skirts an alluvial fan gaining elevation quickly until it is a bit above two thousand feet at Emigrant, a campground and rest stop. From there, take the Emmigrant Canyon Road and follow it, gaining elevation the entire way. At one point the foundation of an old mill appears on the south side of the road and the gravel road to Skidoo is about a mile later.

The gravel road to Skidoo is a winding, clothes washed rutted, and occasionally blasted from a sheer cliff face. A few miles from the road entrance the telltale piles of rock betray the presence of mining. Some of the infrastructure has even been preserved by the park staff. This small head frame still has the sixty foot shaft is still open and timber supported with a serviceable ladder. The entrance itself had been blocked by a cable mesh rock bolted to the shaft walls.

A number of exploration holes were present and curiously followed a outcrop of a quartz vein in the granite bedrock. A little shack was built on the other side of the valley. The mineralization I could find in the piles were open vein fill crystals of some white mineral that had a botryoidal habit. There were small yellow sulfide crystals mixed in, possibly pyrite or tetrahedrite and a dark accessory mineral in the white quartz veins. It looked a lot like the gold vein I found with a metal detctor in Quartzite a few years back.

Continuing down the road, I discovered the town of Skidoo, an old mining town at the top of the world above the Death Valley. There was a sign marking the site and hundreds of mine workings in the surrounding hills. All the buildings had been removed and there was no visible evidence that the place had once been home to dozens of large buildings less than one hundred years ago. The sign did have a few black and white pictures of the valley from the the towns heyday. Investigation of the quite large workings in the granite nearby showed backfilled trenches or gated adits.

Here is a nice one pager website on Skidoo.

I ended up camping nearby that was certainly not in the posted "Day use only: No camping" area. I set up our large family tent on a roughly flat area before the looming clouds and dark arrived. Between the elevation and oncoming storm it became quite cold. Despite the four season tent and Idaho-class cold weather gear I ended up having a bad night. The wind blew the tent down, although to be fair, the water stayed mostly outside.

When the sun finally came over the horizon it was still raining and gusty. I managed to stuff the sleeping gear and muddy tent into the back of the jeep and get off the mountain before the rain turned to snow. The bad weather really put a damper on the plan to hike out to some of the more remote mine workings.

On the way out I snapped a picture of the Mesquite Flats Sand Dunes during the rain and it can be compared to the picture I took a few months ago when the weather was ideal.

Normal

 

With Rain

Death Valley is a great place when the weather is nice. I hope to get back there one of these upcoming weekends when the weather improves but before it gets too hot later this spring. I love the idea of being able to drive out of the bad weather. It didn't work out this time but I am hopefull that it will work sometime in the future.

Paranormal Science. A contradiction?

Today, I posted a question on Facebook for my scientifically minded friends: Is there any science to be done in the paranormal? The responses ranged from a comment about how some science is perceived to be nearly paranormal itself to a hesitant yes with the qualifier that the scientific work needs to be done with extreme detail and care. No one held the strong opinion that science and the paranormal are immiscible, which I thought was interesting. 

What is the definition of Paranormal? A new book called Paranormal America answers that question. Professors Christopher Bader, F. Mencken and Joseph Baker, sociologists from Baylor University, gave a definition for the Paranormal on the most recent Mysterious Universe podcast. Paranormal is loosely defined as unexplained phenomena that is not accepted by science or religion. By definition then, anything that is agreed upon as the Paranormal is, a priori, outside the realm of valid scientific investigation. 

In the interview, the two authors gave an overview of their Gallup pole results and field work investigating the paranormal. The reason their work is impressive is because it uses science to study the only part of the paranormal that can be scientifically analyzed – the sociological aspect of the paranormal. Why do people believe? How many people have paranormal beliefs? Are there distinct populations of paranormal believers?

The interview was incredibly interesting, I highly recommend taking a listen.  http://mysteriousuniverse.org/2010/12/episode-425-mysterious-universe/#more-3796

There were a few highlights from the interview that I thought were worth mentioning:

• After a Gallup poll that was crafted to minimize bias from either paranormal believers or those who reject the paranormal, a significant population (about 2/3^rd) of Americans would admit to believing in some aspect of the paranormal.   
• There are two populations of paranormal believers: The type that want to take an active roll in discovering things like UFOs or Bigfoot or ghosts in the external world versus the type that are concerned with the self, or the interior world with an interest in astrology, self healing, and the like.
• Men and women have a similar predilection toward paranormal belief, but men tend to have more of an external focus when women are more concerned with the internal.
• In a scale ranging from atheist to orthodox religion, both endmembers had the lowest potential to believe in the paranormal. The somewhat religious people who were open to other answers about religion were the most likely to believe in the paranormal. Atheists did not believe in the paranormal because they felt it was too similar to religion. The orthodox did not accept the paranormal because it interfered with their own beliefs, which often had strong paranormal aspects.  

The discussion continued with a look at how wealth and education influenced paranormal beliefs and how the beliefs of the nation may change over time. Another interesting question they raise is what the results of a similar survey would be in a country without the same deep-seated religious beliefs of the United States. The takeaway for me was that a huge percentage of the population believes in some form of woo. 

If the definition of paranormal means that it is a subject that is outside of science, then sociology is the only science that can study the paranormal by investigating the motivations of the people who believe in it. Another key point to remember is that studying the people who believe in the paranormal says absolutely nothing about the validity of the paranormal itself. If all the people in the world believe it is flat, does that make it true? Clearly not. The real question, then, is what happens when a non-scientific, paranormal idea grows to be so widespread in a population that it becomes the norm? What influence does that have on scientific thinking when an idea is so ingrained that it is not challenged? Is this the point where we need to have faith in the scientific process to break through a sociological barrier?

Here is a link to the book with the Mysterious Universe affiliate code. I am thinking strongly about making this my next read. http://www.amazon.com/gp/product/0814791352?ie=UTF8&tag=mysteruniver-20&link_code=as3&camp=211189&creative=373489&creativeASIN=0814791352

That's one small step for man, one giant leap for robotic lunar mining-kind - Part 2 Exploration

Exploration is crucial for any mining operation, including one on the moon. In this case I use the term exploration as a mining term which includes activities that determine whether or not a mineral or element is present in a prospective mining area. But I think anyone would agree that all places on the moon are not made equal when it comes to mining. Take, for example, that the moon has a surface area a little bit smaller than that of the Continent of Asia. Do you think that I could start a mine anywhere in Asia and find what I am looking for?

There needs to be some way to narrow down the possibilities when selecting the site. A few givens will be obvious immediately, especially if we are looking for water. If water is the target mineral, there are a only few large craters at the northern and southern hemisphere that are shadowed all year long. But, if we are hunting for helium-3 or metals or sulfur, we need to do something to figure out where there is more..say, sulfur, and make a plan to go there. In this case, I want to use sulfur for the remainder of this discussion because it seems to have the most practical use as a cement in a type of lunar concrete that has been proposed.

The Exploration Geologist on Earth has a number of tools in his bag. He usually starts with a series of maps that help him narrow down what likely geologic structures might have concentrated the minerals of interest and whether that particular unit occurs in one spot or extensively. Aerial photographs are often used for this purpose initially. Then as targets are developed, multispectral spectrographic imagery could be used to look for telltale signatures of the presence of a particular mineral or element (depending on the technique). Additionally both types of maps could help him determine if there are helpful outcrops that he could go and sample to verify.

Where would we find such maps of the moon? All the results from the 1994 Clementine mission, which includes UV to visible and Infrared Images are available online for any interested parties. http://www.lpi.usra.edu/lunar/tools/clementine/  Also, the more recent Lunar Reconnaissance Orbiter has a suite of instruments that can detect and map any number of minerals that could be used to narrow down a mining target.  http://lunar.gsfc.nasa.gov/index.html The limitations are numerous and could include the specific element of interest (Clementine looks like there are 5 spectral bands available, which is quite limiting) and the pixel resolution of the instrument itself – some of the data is only available on the kilometer scale resolution, much larger than a pit-type mine could be.  The LRO has a much better camera that has imaged tracks and equipment left behind from the Apollo missions. This scale and wider are useful for mining applications.

As a starting point, these satellite images of the moon would be used to determine areas with the highest concentrations of the ore of interest. The preliminary results of the mapping could be used to estimate a volume of ore present in the target location if some work was done in advance to calibrate the spectra to a given mineral concentration.  

The next step would be to get boots on the ground and begin sampling to verify the results of the spectral mineral map. In this particular case we could get lucky and find that one of the Apollo missions sampled material that happened to be spectrally very similar and use the samples that they collected as a type of verification. Alternatively, the meteorite bombardment that pulverized and mixed the upper layer of the moon, the regolith, could be so well mixed that there is not enough variation to be picky. In this case, any target area with a sufficiently deep and extensive regolith could be adequate. However, the odds are that the people who are doing the mining are going to want to optimize their mining by finding a location with even incrementally better concentrations of sulfur. And the only way to verify that is by getting on the ground and developing a sampling plan.

Sampling is a surprisingly complicated subject. In the easiest case, you have a guy who walks around with a shovel and bags and a map and picks up samples roughly evenly distributed across the target area. However, there is a dark and sullied corner of science that deals with how many samples are statistically required to get a representative understanding of the material present.  The statistics are driven by the extent of the ore body, the structural limits of the ore body, the consistency of the sample results, the magnitude of the sample results, the sensitivity of instrument measuring the ore concentration, and any secondary elements that could mask the presence of the ore, among others. Reading through this list it is easy to see that planning for the correct number, spacing, and depth of samples requires knowledge of the ore body that a geologist may not have until after the sampling has started. This puts the geologist in charge of the budget in an odd spot where planning for the adequate amount of data may not be possible without clairvoyance or a good deal with the devil. In this case it is always good to make a facts-based estimate for the number of samples and then double it.

Another kicker is precisely how we sample. There are a couple different methods that immediately come to mind. We have already discussed the idea of taking a shovel and filling a bag. There are also small tools to core out shallow boreholes from soft material such as regolith. And then there are the big boys, using a drilling rig to collect a deep continuous sample of core or chips.

Here is a cartoon of a layer of ore-bearing regolith sitting above a layer of barren regolith. The ore is concentrated on the top by, say, cosmogenic processes – solar wind has been enriching the upper foot of regolith with He3 for the past billion years with little interruption.  Each type of sample is shown, a small shovel excavation, a deep shovel excavation, a small borehole and a deep borehole. The benefit to a shovel excavation is that it is quick and easy, but the results can be misleading since it is artificially sampling the upper volume of the layer more than the base and so the results would have a somewhat higher concentration bias. The deep shovel excavation results would dilute the concentration by introducing the barren regolith beneath. The small borehole provides an evenly distributed sample that looks to be ideal for this application. Deep drilling would not be necessary for sampling a shallow ore body. The appropriateness of these sampling methods is largely dependent on the type of deposit that exists and removing bias can be a process that takes time and planning and often, can’t be perfected until after mining has begun.

The results of this sampling plan would then be turned into a map that shows the concentration of the mineral or element present at each sampling location. The maps could be contoured or used in a mine modeling program that extrapolates the results between boreholes to try and better determine the extent of the deposit. Once a sampling plan is completed, the concentration and total extent of the ore is defined, and then the first stages of mining are ready to begin.

They don't us Lunatics for nothing

In researching the next post I found this website, www.moonmining.com Pure Gold...er, I suppose that's Pure Moon Dust for the rest of us. Or "Lunar Regolith" for the "scientists" amongst us.

http://www.moonminer.com/Lunar_regolith.html

I have to admire what he has done here. In the introduction he states that "There are no definite processes for extracting metals and gasses from the regolith to be found." I think he is largely correct on that point, but that is where we part ways. The remaining five hundred pages of text are a lot of crazy speculation on blue sky magical thinking about how the human race can eventually reach the stars. The moonmining website is a bit like the goatee-wearing mirror of my whitepaper in the evil anti-universe. This topic deserves an experienced hand and consideration of the technology and resources that could make mining on the moon a reality if enough support ever made it a priority.

The author of this website could, in fact, be the same guy I met at the party in California. I don't know. In all honesty, I will, in fact, be using the references that this author has so diligently researched in advance of my efforts.  

Here is another great idea that I love. At the Lunar and Planetary Science Conference Fries and Steele from the Carnegie Institute propose sending a rover to the moon with a raman spectrometer to look for meteorite fragments in the regolith.

www.lpi.usra.edu/meetings/LEA/.../FriesMDF_Lunar_wksp_07.pdf  Warning! PDF

This harkens back to brief but exciting days of my most recent graduate school field work using a portable handheld raman spectrometer to analyze carbonates in the Mojave desert.The absolutely best part of this abstract is that they named the probe Moonraker. Ala James Bond. Brilliant! The next space instrument I dream up to send to Mars shall be called Goldeneye!

That's one small step for man, one giant leap for robotic lunar mining-kind - Part I Introduction

This is the first of a series of posts where I intend to explore the technical hurdles of mining on the Moon. It is also a living document, like a ball of clay that might need to be reworked until it is just the right consistency to begin pottery. As such, I ultimately want to get this collection of posts into a form that could be published as a whitepaper for lunar mining. It might not be the only solution, but I would like this to be thorough enough to work if implemented.

I met a guy at a party in California during my intern years at Ames Research Center in the summer of 2003. This guy had kind of long shaggy graying hair and sort of dirty clothes and smelled strongly of coffee and cigarettes from a full arms length away. I remember wondering at the time what he was doing there and if he had just wandered in to the gathering from off the street. When I introduced myself he reciprocated and told me he was working on first principles analysis of going back to the Moon. He told me it was his goal to develop an entirely new way of looking at both traveling to and staying at the Moon and that involved retasking and reusing equipment, getting creative with ways to travel on the surface and ways to exploit the Moon's resources once we got there. There are going to be rovers built from spare parts that roll over any obstacle on the Moon’s surface and they will be modular so they fit together to make a habitable base. We will mine the surface not just for the helium-3 that can be shipped back to earth to pay for the operation, but the regolith will also be processed for all the building materials and life-giving elements that a colony needs. This vision of colonization of the Moon was entirely unlike anything that happened during the Apollo mission. It was a vision of sustainably living on the Moon’s surface with a minimum amount of resupply or support from Earth.

This chance meeting has stuck with me ever since largely because it was surprising that this crazy, homeless man had a good enough story to fit in with the rest of us at the party but also because he was right. The next time the human race goes to the Moon, it should be to stay and it should look dramatically different than the first time - the next effort should not be “flags and footprints” so much as dust, sweat and tears.  

Living off the land is the Zubrinian mantra (from The Case for Mars) for how to make sustainable exploration work. In long term economic exploration of the Moon mining is going to be an important part of making the effort worthwhile. One of the previous topics I have mentioned is using a unique formulation of concrete for construction on the Moon. This would require developing a way to mine and purify sulfur before any construction can begin. A different, more popular idea is paying for the missions by mining for helium-3, an isotope that is rare on the Earth, but relatively abundant on the Moon’s surface and can be used to dramatically improve nuclear power production using fusion. I have also heard arguments for mining metal from a thin layer of cosmogenically altered rock on the surface, oxygen bound in the minerals that compose the surface rocks, and silica in that same rock for solar panel production. Mining will also probably be required to extract and purify cometary water from the ever-dark craters that have preserved the ice on the north and south poles. I am going to discuss mining on the surface of the Moon in general terms because it encompasses all of these options. Going down into the depths of the Moon is a different story for a different day.  

There are a few key questions that must be answered before going forward. First, is mining possible on the Moon’s surface? Second, if so, is it more economical than shipping every pound of oxygen, water, food, and construction materials required to sustain life from the Earth? There are likely a wide range of viewpoints that exist varying from yes to no for each question. I think the task of mining on the Moon’s surface is possible, but that it is a much more complicated task than any NASA scientist has ever considered and that could mean that mining and processing is not an economical alternative to flying every piece of a habitable base to the Moon…at least for the forseeable future.

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Mining is a process

In the old days it was drill, blast, muck, haul. Over and over again, as fast as possible. In recent times, the process is basically the same, but with a few extra steps along the way. And I am convinced that the process is the same here as it would be anywhere else materials must be extracted. The big differences are in the details of the individual steps of the process. 


Today mining has two essential tracks, operations and engineering. Operations could occur without engineering but at the risk of long term disaster and failure of the mining operation itself. Each track has tasks that begin with defining an ore body during exploration and go through the steps of mining and processing that ore until it can be milled and a final product is produced. In this case operations includes both the mining and the milling staff.  As the mine progresses the engineering and operations groups work together to optimize the mining operation. This is true for precious metal mines, coal mines, iron mines, and aggregate mines. Below I have a rough diagram that outlines the critical steps for a mine process that would result in, say, sulfur production.

This is a lot of steps and there are very specific pieces of equipment that are used for each step. For example, a medium sized gold mine might have thirty large dump trucks and three or four pieces of loading equipment to extract enough ore to feed a mill and haul waste to dumps. The mill for a mine that size will have a footprint of several acres and be many stories tall with an electrical consumption equivalent to a moderately large neighborhood. The total gold production that might come from such an operation after a full year of production could be shipped out in one armored van.  

How does this analogy transfer to the Moon? Does each step require a crew and equipment or can they be combined into one super miner/miller machine that does the job with an operator or a robot at the controls?

In the movie Moon, Sam Bell, played by Sam Rockwell, is a one-man crew living on a lunar base outpost mining helium-3. His mining equipment are house sized rovers that traverse the surface scooping up regolith and milling it onboard. The shipments of helium-3 are rocketed back to Earth in small containers that are easily manhandled by a single person, surprisingly similar to the gold mine scenario discussed above.  

There is video of this miner in operation at IMDB here http://www.imdb.com/video/imdb/vi1306264089/ Moon 2009 is definitely worth watching, I highly recommend it. You can catch the full show on Netflix streaming or buy it on Amazon.com.   

I love this vision of mining. It is the right idea for surface mining in loose, fine grained material that is rich in ore close to the surface. Instead of taking a block of material by scooping it into trucks that haul it to a mill, it shaves off the upper foot or so, separating the big rocks and hurling them away while processing the good stuff on the inside and dumping all the waste rock out the back.

A scenario like this might actually work for mining helium-3 or water from the regolith. There are plenty of designs for continuous mining equipment that can slowly move across a flat, ripped surface and load the dirt via conveyor to a waiting truck. 

Photo from http://www.ene.ttu.ee/maeinstituut/publications/Development_Valgma.htm

It is not difficult to imagine adding a module that heats up the ore regolith to a temperature high enough to drive off a significant fraction of the helium-3 or water and collect it in some kind of a condenser.  The remaining waste rock is simply cast aside. This idea works because helium and water are relatively volatile and simply warming up the rock is enough to collect it.

 But what about sulfur, or metals, or silica that are bound much more tightly to the rock and require significantly greater temperatures to be liberated? Sulfur is more volatile than the others. If the grains of sulfides (the class of mineral that sulfur would exist in basalt type rocks on the moon) could be exposed in the ore by crushing the rock to the grain-size of its constituent minerals, then the sulfides could be concentrated and heated up and exposed to a reducing agent to react with the metal in the sulfide. On Earth, carbon in the form of coal is added to the fiery mix to drive off the sulfur as a sulfur oxide gas. I am not sure what chemistry could be done using the materials on the moon to make that reaction go – it is unclear if heat alone is enough to drive the reaction.  

That is it for today. We looked at the mine as a process and speculated a little about the validity of some recent science fiction that seems closest to the mark. The next post is going to focus on the first stages of exploration and sampling that will be required in order to define an area that can be mined.   

The Great Meteorite Hunt Debacle

Meteorite hunting can be a cruel mistress. Last week I was travelling through Austin Nevada during a trip to my new place of employment. I was a little early to check in at the hotel and decided to visit a nearby playa basin to hunt for meteorites. I was also testing the hypothesis that meteorites could be found nearly anywhere rocks are uncommon and easy to find – salt flat…which was bolstered earlier by reviewing the Meteoritical society’s database of known meteorite find locations.  

Google map of the Meteoritical Society's database of meteorite finds.

A front had moved through and there was a fresh coat of snow on the ground a few inches deep. Clouds were boiling on the edge of the basin and zero-visibility blizzards came through more than once that afternoon.  I turned off the gravel road and took the truck down the muddy alluvial fan towards the salt flat. After a fun 270 degree spin, I parked and started hiking. Looking around the valley, the salt flat was surrounded by mountains composed of metamorphic and basalt rocks.  

Google map of Nevada salt flat

The snow was deep enough to cover most of the ground, but any of the small bushes or scrub had a bare spot at the base. As I walked I noticed that there were no rocks to be found. I must have walked two miles without seeing a single hard rock. Any mud balls or sticks that I came across were sticking up through the snow and transmitted enough ground warmth to melt a bare spot. I figured that if there was a meteorite (or random rock) I would have seen it.

Salt flat

And of course I eventually ran across a couple of tires, thousands of mudballs and sticks, and one rock! I got very excited and immediately picked it up for a look. It was about the size of two baseballs, a greenish colored exterior with red and yellow-greenish mottling and dark veins on the exposed interior. There was also a clearly visible rim on the edge. There are a lot of reasons to think this was a meteorite! Here is a website that describes rocks a lot like mine. 

The coloring of the interior is similar to other weathered meteorites I have seen. The reddish color is rusted iron and the green comes from olivine or chondrules. The visible rim was similar to the alteration associated with a fusion crust developed as the meteorite hurtles through the atmosphere and melts the outer surface. If these characteristics were true, it would be consistent with an LL type ordinary chondrite, the most common type of meteorite found.

Figure 1 - Weathering Rim

Figure 2 - Exposed interior top-left, exterior bottom-right.

Figure 3 - Mottling and veins

Closer inspection of the rock convinced me that the rock was not a meteorite. The greenish color of the exterior is very unusual for an ordinary chondrite. The rim on the edge looks a lot more like a weathering rind than a fusion crust. Fusion crusts are typically black and thin. Weathering rinds occur because a rock travels a long way and is exposed to the atmosphere and water that break down the minerals on the outside of the rock. You might expect the crazy random rock that survived the trip all the way down the hill to have a little extra weathering. Finally, the mottling could also be explained by the hematite and plagioclase or olivine that are found in basalt, a rock that could be found uphill. Meteorites can have veins, but terrestrial rocks are a whole lot more likely to have them.

There is one final test. In all honesty, as I type these words I have not yet taken a magnet to this rock. If the rock does have metal in it, the magnet will be strongly attracted to it. The red hematite is an oxide of magnetite, which is also metallic, and could also attract a magnet. However, the strength of the attraction should be easy to tell the difference. Ok, here goes. Nope, not magnetic.

Alright, that’s the test. Its not a meteorite. Meteorite identification is not for everyone, but I like the process. If it had been a meteorite as far as I could tell, the next step to confirming it as a meteorite is to send a portion of it to the closest geology department with a meteorite specialist. At Arizona State University, this would be the ASU Center for Meteorite Studies. http://meteorites.asu.edu/ Once there, a specialist would look at it, considering the mineralogy and structure of the rock. If it passes, the specialist will use an instrument called the PIXE, Particle Induced X ray Emission spectrometer, will be used as the final test to determine if the iron to nickel ratios are consistent with a meteorite. At that point, you then have a real meteorite!

          

How to Stalk Your Scientist Colleagues - The NASA Astrobiology Announcement Revealed! Arsenic life exists!

Sadly, NASA’s press announcement failed to be the alien UFO disclosure we were all hoping and wishing for. Even the more reality-based speculation about discovering evidence of microbial life on Mars or Titan turned out to be a bust. But one lonely blogger did some foot work and guessed the results of the paper nearly a full day in advance of the embargoed publication date. While the majority of the people on earth probably do not understand or even care about the result, it is probably the most significant finding since the components of DNA were originally parsed.

There was a Star Trek Episode where the crew finds a silicon based life form buried in a deep mine on an alien planet. (Geek Alert Season 1, Episode 25 The Devil in the Dark, the silicon based life form is the Horta)

(Photo from http://en.wikipedia.org/wiki/The_Devil_in_the_Dark)

The idea was that the carbon in our DNA can be replaced by silicon, an atom that is right above carbon on the Periodic Table, and so is capable of performing many of the same chemical reactions. While nobody has found a silicon DNA or protein component, this new paper announces a similar substitution of a life-sustaining atom in a real-live Earthling bacteria.

The Science paper, announced today in a NASA Press Release briefing, states that the phosphorus found in DNA is replaced with arsenic in a strain of bacteria found in Mono Lake, CA. Here is the Science abstract. http://www.sciencemag.org/content/early/2010/12/01/science.1197258  But there is a significantly more detailed summary on the Arizona State University website that was pointed to me by my ASU mentor Ariel Anbar, a coauthor. http://asunews.asu.edu/20101202_arsenic

The significance of the announcement is that if substitutions for life-necessary elements can be found, then it is feasible that life processes can occur by entirely different chemical paths than what we generally find here on earth. Instead of looking for a fairly strict ratio of elements that we find in DNA, the search for life must be expanded to include any number of possible permutations that could lead to life. And the best part is that, at this time, we can not necessarily predict what elements will lead to life.

All in all, very cool. It tickles me a little bit to have worked in one of the labs that produced these results, even for a few months, without success on my project. Ariel’s a good guy and I anticipate many more significant results coming from the Keck lab at ASU.

Also, as a note, one of the big side issues that came out of this story is how the Science and Nature embargo system in tandem with the highly suggestive NASA press release caused trouble. I have a strong feeling that the scientists who wrote the paper felt like they were hogtied during the embargo while crazy speculation bounced around the internet. Additionally, the press release was extremely suggestive and lead to a lot of hype in a fairly technical topic that may have harmed the public confidence in science. I hope there are some lessons learned from this announcement that will be considered in future press releases.     

Concrete in SPACE!

Concrete is awesome stuff.  If there was one thing I wish I had studied more as an undergraduate, it was concrete. Now concrete is used everywhere here on earth, but is it a suitable material for construction on the Moon? A relatively new study looks at that possibility and that paper is summarized in the New Scientist. http://www.newscientist.com/article/dn14977-astronauts-could-mix-diy-concrete-for-cheap-moon-base.html

Back when I was an undergraduate at the South Dakota School of Mines & Technology, concrete was a big deal. The Civil Engineering department students made a canoe out of concrete and raced it in a national championship – winning more than one of the years I was there. We even proposed a project to NASA’s Reduced Gravity Student Flight Opportunities Program (RGSFOP) where students would fly in the Vomet comet KC-135 for the purpose of mixing high strength, fast cure epoxy to determine whether the concrete mixture would have a different chemistry while curing in Zero-G. But it was always clear to me that Concrete was a somewhat ambiguous substance to most people, subject to misunderstanding and generally eschewed.

The first major misconception is the difference between concrete and cement. The terms are generally used synonymously by the public, but there is a major difference. Concrete is loosely defined as a mixture of cement, aggregate, and sometimes, water that are mixed to form a hard, strong building material. The official civil engineering definition (found on CivilEngineeringterms.com, http://www.civilengineeringterms.com/civil-engg-construction-and-graphics/definition-of-concrete-concrete-history-and-strength-concrete-popularity/) is a little too strict, mentioning specific types of cement, including Portland Cement, the most commonly used cement. If that was, in fact, the case, the Concrete Canoe competition would not be possible as the canoes are built from epoxy as the cement and styrofoam pellets as the aggregate. So, by the loose term we could also consider jello with fruit cocktail as a very weak, tasty concrete.

The other major misconception is that concrete is not a sophisticated material. While in its simplest form, concrete was a technology accessible to ancient civilizations – I remember visiting Egypt and all the buildings on the outskirts of Cairo were poured concrete with steel rebar sticking from the roof (the buildings were unfinished for tax purposes). Heck, even I am excited about someday building my own concrete counters into my house – and if I can do it… Modern day concretes are stronger in compression than, I think, any other building material, and creative designs allow for concrete to be used in long spans and towering structures alike. The concrete canoe floats – how is that not sophisticated?

So that being said, is concrete a suitable building material on the moon? Well there are some plusses and some minuses.

The Plusses

Concrete is only really strong in compression. Thanks to modern day building designs, spans can be built by steel reinforcement that brings a long span normally in tension to compression. The significantly reduced gravity of the moon means that concrete can cover much larger open distances with reinforcement than on earth. Since the material gains strength by adding thickness, extra thick walls are also consistent with the need to add particle shielding for any human habitat on or near the surface.

Finally, there is some interesting ideas about how raw materials found on the moon’s surface could be manipulated to make concrete using the loose description we talked about above. In this paper, elemental sulfur could be used as the cement to bind raw aggregate regolith from the moon’s surface to make a kind of concrete. The process is simple, heat up sulfide rich rocks to extract the raw sulfur. Melt the sulfur at it’s low melting point (somewhat above 113 degrees C) and mix it with the aggregate. This mixture of sulfur and moon rock would behave something like asphalt at temperatures that are comfortable to people.

It seems possible that this could be done and at a large cost savings compared to bringing in steel or other prefab modules. If all the materials are present, the only thing an astronaut construction crew needs to do is generate energy (easily done from harvesting solar energy or nuclear reactors) and bring the manufacturing equipment to do this work. Scouting out suitable locations that have the correct dirt is also important, but feasible even today. After some period of time, the cost of building from processed materials onsite can be much less than the cost of shipping in every pound of building materials.

The Minuses

How feasible is bringing the infrastructure to do this kind of work on the Moon? It took twice as long and a hundred times more than anticipated to build the International Space Station. The equipment to create concrete on the moon must be even more sophisticated and reliable than anything we have sent to space to date. At this point, the space industry has expertise in building modules that fit together. I might agree that a new technique would be required to have real outposts on the Moon, but I think that many of the first outposts will focus on the task oriented prefabbed habitats that are similar to the ISS.

How does concrete behave in a vacuum in reduced gravity? This is a question that I do not think has been answered. While I think the paper that this story is based on was well done, I suspect that it was not done in temperatures or the kind of vacuum that exists on the moon. I am certain it was not done under reduced gravity conditions that could have a significant effect on the strength of the material. Even the simplest idea of how do you handle an asphalt-like substance on the moon makes me wonder if it is possible?

I think this is a fantastically interesting topic. If travel to the moon becomes routine within my lifetime, I hope to hear more about building with concrete.  

How to Stalk Your Scientist Colleagues - Speculation on the NASA Astrobiology Announcement

There was a pre-announcement at NASA HQ today on a big Astrobiology announcement coming this Thursday.  This story is too good to pass up. First, I want to look at the woo crystal ball and predict what will hit the news and then take a deeper look at what the announcement might actually be about.  Looking back at the old astrobiology questions is fun and interesting.

http://www.nasa.gov/home/hqnews/2010/nov/HQ_M10-167_Astrobiology.html

The Woo Crystal ball

I read about this story first from Phil Plait, the Bad Astronomer on his blog earlier today "Snowballing Speculation over a NASA Press Conference", and then by a movie director friend on Facebook. By that time, I figure the story must have hit the mainstream.  The Woo Crystal Ball says that an announcement from NASA about Astrobiology MUST be about the discovery of life on a different planet, maybe one of those rovers finally caught undisputable proof of a little green man or a Mars weed or something…some will say that it will be final disclosure that alien visitors have been with us on Earth for some time now.

This is silly. But I do hope that this week’s Mysterious Universe will be recorded before the Announcement so I can get a summary of what people are saying.

What the Announcement Might Actually Be About

The NASA Press Release gives very few details, but it gives a list of scientists and this sentence describing the meeting “to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life”. The potential of this announcement rings of the ALH84001 announcement, for which President Clinton made a formal announcement including this statement “If this discovery is confirmed, it will surely be one of the most stunning insights into our universe that science has ever uncovered. Its implications are as far-reaching and awe-inspiring as can be imagined. Even as it promises answers to some of our oldest questions, it poses still others even more fundamental.” Well, sir, this might sound like an ALH84001 announcement, but it is NO ALH84001.  

As Phil Plait notes, important publications typically have an embargo period where the announcement is held back until the publication date. This is maybe to keep up sales of Nature and Science? In fact, the press release notes that this announcement is under embargo until 2:00pm on Thursday. Because Science, the journal, only reports significant findings, the announcement must be on the results of an aggressive and interesting study. But what could it be?

My first thought was not to speculate about what kind of research is being done in astrobiology or what the open questions are in the field. Nope, my first thought was, what does it take to stalk a scientist? Not very much, below I have the search results of typing in the five authors’ names into Google and tracking down descriptions of their work.  

-     Mary Voytek, director, Astrobiology Program, NASA Headquarters, Washington 

http://astrobiology.nasa.gov/directory/profile/4886/mary/voytek/

‘aquatic microbial ecology and biogeochemistry. She studies environmental controls on microbial transformations of nutrients, xenobiotics, and metals in freshwater and marine systems. She has worked in several extreme environments including Antarctica, hypersaline lakes, deep-sea hydrothermal vents, and terrestrial deep- subsurface sites. At the USGS, she heads the Microbiology and Molecular Ecology team. She has conducted deep-biosphere studies at the Chesapeake Bay Impact Structure.’

-     Felisa Wolfe-Simon, NASA astrobiology research fellow, U.S. Geological Survey, Menlo Park, Calif. 

http://www.ironlisa.com/research/

“a background in molecular biology, biochemistry, and phytoplankton physiology to uncover the sequence of events that shaped the evolution of the modern oceans phytoplankton and life itself.”

-     Pamela Conrad, astrobiologist, NASA's Goddard Space Flight Center, Greenbelt, Md. 

http://astrobiology.nasa.gov/directory/profile/201/pamela/conrad/

Conrad, P.G.,  et al  (2006).  The Bread-crumb trail: distribution of organic chemical biosignatures from cryptoendolithic communities on the surfaces of Arctic and Antarctic sandstone rocks. Astrobiology, 6(1):167.

-     Steven Benner, distinguished fellow, Foundation for Applied Molecular Evolution, Gainesville, Fla. 
http://www.ffame.org/people/sbenner.html

The origin of proteins and nucleic acids 
Ricardo, A Benner, SA 
Planets and Life: The Emerging Science of Astrobiology, ed. Woodruff T. Sullivan and John A. Baross, Cambridge University Press 154-173 (2007)

-     James Elser, professor, Arizona State University, Tempe

http://sols.asu.edu/people/faculty/jelser.php

  “In more recent work he has extended the work to investigate the connections among C:N:P stoichiometry, growth rate, rRNA physiology and genetics, and ecological dynamics in diverse biota and ecosystems and to evaluate the application of these ideas to tumor dynamics. Currently, he is an active member of the ASU’s NASA-funded Astrobiology project “Follow the Elements” and a co-organizer of ASU’s Sustainable Phosphorus Initiative.”

What do these descriptions have in common? What would the focus of a collaborative research effort of one or more of these folks include? Clearly, they all have an emphasis on microbiology, DNA, and evolutionary biology with an emphasis on astrobiology. While it is unclear to me precisely what kind of research this announcement is going to be on, it is clear to me that it is going to be a study on evolutionary geobiology. The youngest scientist, Felisa Wolfe-Simon, a NASA Astrobiology research fellow with grad time working at Dr. Ariel Anbar’s lab at ASU, had the most compelling blurb on her blog “To unravel details regarding the co-evolution of life and Earth.” I think they are going to announce a fundamentally different type of DNA or life process – maybe a non-carbon based chemistry that would support life. How cool would that be?

We’ll see and I’ll follow up with a little blurb Thursday evening!

Muon Telescopes...Attack! Part III

I got excited about Muon Telescope design because I think that the muon flux, and the neutrino-detection noise, will vary significantly at DUSEL. The variability is due to the topography and the geology of the ground above the 4850 level campus where the first muon telescopes could be installed. Today, I want to look at a couple more parameters that could be important.  

Here is a cross section of the mine showing geology. I pulled this from the DUSEL.org website which is a fantastic resource for DUSEL information, including full publications of the geology of the Northern Black Hills (shh, don’t tell anyone). http://homestake.sdsmt.edu/Resources.htm

Here we see the very complicated geology that was encountered during mining. The complicated folding and squeezing of the various layers occurs in all three dimensions with more than four large scale deformation events. Each layer has a different geology, and one would expect a different meters of water equivalent (M.W.E.) shielding capacity. In this figure the topography does change, I included a line that shows the shortest path to a hypothetical 4850 level campus is not vertical, but is in fact about fifteen degrees off vertical. However, the difference in length between those paths is small at <10%. I also drew another muon path at about 45% off vertical that illustrates the much longer path through the rock that it must travel. That additional travel time in rock will increase the odds of a muon interaction with a mineral particle, and thus the increased odds of attenuation for any particle coming in at an angle.  The little inset diagram shows a Gaussian curve that should roughly describe the distribution of muon flux from vertical (roughly maximum) to horizontal (minimum).  I might expect to detect muons even if the muon telescope was oriented horizontal, possibly due to the curvature of the earth or the persistence of the particle.

As we have discussed before, a muon telescope is two scintillators with photomultiplier tubes to count the photons coming off the scintillator when a particle interaction occurs.

The geometry of the telescope is simple. The two scintillators are separated by some distance. The size of the detectors and the distance between them determines the maximum angle off of vertical, theta, that an incoming muon could create a signal on both detectors. Another way of saying this is familiar to photographers, theta is proportional to the field of view of the telescope.

The further apart the scintillators are spaced, the smaller the field of view - primarily because the odds of an incoming muon will have the correct angle to hit both scintillators. Both scintillators may get the same number of hits, but by measuring the time interval of the hits, single muon particles can be traced and differentiated from decay of,  say,  thorium on the cavern walls that spews out random ions that could be detected on both scintillators at roughly the same time.

Lets look at it using a fancy Venn Diagram.

Both scintillators are triggered all the time by random ions, cosmic rays, and lab gremlins all the time, some we want to measure and some we don’t.   The ratio of good signal to bad signal is bad in both cases, but if the telescopes are separated, the magnitude of bad signal is small, but so is the magnitude of the good signal.

So, is there anything we can do to optimize the design of the telescope so that it minimizes random noise and loss of signal because the muons decay between scintillators? There are a number of parameters we can plot up to look at this question. Using the muon telescope cartoon, we can come up with the math to solve for the muon flight time between detectors and also look at the angular field of view. The angular field of view should be proportional to the muon flux with some influence by that flux distribution that we showed before.

On the left axis, the travel time of a muon is plotted. For the case where a muon is coming down vertically, the wider the distance between scintillator paddles, the greater the travel time – it is a linear relationship. However, consider the maximum diagonal travel distance a particle could travel and still hit both scintillators. This differential distance increases as the paddles are brought closer together and as the paddles are increased in size. In this figure, the largest paddles placed one paddle-width from each other on the low end to find the maximum differential. The maximum travel time has a variance of more than 100% and it is actually larger than the 5 ns detection limit Mark told me about a while back. In that case, a muon travelling diagonal would not have been counted. However, the effect quickly drops off with smaller paddles separated by larger distance, maybe 4x the paddle diameter could be negligible depending on the required accuracy.

On the right axis, the field of view (FOV)  in degrees is shown. The closer the paddles are together, the larger the FOV. As the paddles are separated, the FOV quickly drops away and approaches zero as the paddles are separated.  The paddle separation should be selected to accommodate the shortest muon travel path. Since the FOV is proportional to flux, the farther the paddles are separated, the smaller the muon detection and the greater integration time required.

Finally, the decay time for a muon is about 2 µs = 2000 ns. The longest travel time between scintillators shown on this figure is about 35 ns. The odds of a decay occurring between detections is not zero, but the travel time is small compared to the decay time. It is a bit unclear to me if the 2 µs value is at earth frame or if it is particle frame dependent. The effects of relativity will have the effect of increasing the apparent decay time from the earth frame and, thus, overestimating the number of muons that would be counted.

Badass Amateur Scientist of the Day - Tycho Brahe

If you met a guy in the 16th century who was a Danish nobleman with a metal prosthetic nose (after loosing part of the real appendage in a duel over mathematics), he kept a psychic midget named Jepp under the dinner table, and an elk that died because it consumed too much beer and fell down the stairs... you might think, this is a pretty interesting guy. Alas, he was also the father of modern day astronomy and spent 20 years of his life developing the most accurate and comprehensive dataset of astronomical observations of the age. That dataset continued on after his death to allow Keppler to calculate his three laws of planetary motion, an accomplishment that may have been stained in the blood of Keppler's ruthless mentor.

Now, why does Brahe qualify as an amateur scientist? It is my contention that the professional scientist did not come about until after the Industrial Revolution, and many of the earlier scientists were merely rich people who were looking to understand the universe and find a way to turn lead into gold. What Brahe did was important and revolutionary for the time, but really it was something that anyone could have done if they owned 1% of the wealth in Denmark and his very own island and a castle.

His measurements were all done using a set of naked eye observations using very large instruments of his own design. The key to his success was systematic, rigorous observations of the sky every night. This allowed him to discover a supernova, a new star in the sky - and his measurements were good enough to verify that it was not a planet or other nearby object. He also did lots of other cool things like perform the first survey using the triangulation method - in his case it was of his island where his research compound was located.

The myth of his death was that his bladder burst because he refused to leave the table during a dinner party. But, because he was such an interesting person, his body has been exhumed, not once, but twice in order to determine a cause of death. High levels of mercury were found in his hair tissue collected in his first exhumation. New samples have recently been collected and will be tested for metals and poisons. One hypothes is that that he was poisened by his assistant Johannes Keppler, whom Tycho would not share the results of his work while alive. Keppler is also a badass for maybe having murdered his boss in order to develop his three laws of planetary motion. (http://www.reuters.com/article/idUSTRE6AE31T20101115)

With the death of scientists like Tycho Brahe the world was left with a huge vacuum of personality and the dinner parties have forever since been a little bit less interesting. It is difficult to imagine a more colorful scientific historical figure. If you want to learn more about Tycho Brahe's accomplishments, including his nuclear battles with Space Hitler, you can go to his island museum, the Island of Ven just off the coast of Landskrona, Sweden, or you can visit www.tychobrahe.com.

All my information came from Wikipedia, (http://en.wikipedia.org/wiki/Tycho_Brahe) , especially the part about Tycho Brahe's battles with Space Hitler.