Tuesday, June 30, 2009

Non-violent protest

As the 20th anniversary of the Chinese student crackdown comes and goes, my daughter has decided to celebrate by learning the methods of passive resistance and non-violent protest. The other day, Mrs. Lemming went out, and LLLL did not think that this was a fair or just activity by the leadership of the family. So, she staged a lie-in at the front door, complete with chanting and refusal to clear access to the front door. I suspect that the only reason she didn’t make a sign to wave is that she doesn’t know how to read or write. Her ability to render the message “My Mummy” in print will be limited until such a time as she learns the letter M. She does understand other visual statements, though. He shorts over jeans says only one thing: Until mummy comes back, I’m dressing even worse than dad.


Figure 1. LLLL organizing a lie-in behind the front door.

Where the side shows are lightyears from the main tent...

Carnival of Space 108.
Carnival of Space 109.
Carnival of Space 100.

Monday, June 29, 2009

Back atcha, Lemming

Last week I posted that the entire inner solar system was visible in the predawn sky. The reason for this is that Venus (and Mercury) were in between Earth and Mars. One of the reasons Mars (the dim red dot in the picture) was so dim is that it is on the opposite side of the inner solar system.

Figure 1. positions of the inner planets on June 19. Note that Mars, Venus, and Earth are co-linear.

Of course, any Martians looking back at Earth in the evening sky would see something very similar. Venus and Earth would be close together in the evening sky, with Mercury low on the horizon. Figure 2 shows a simulation.


Figure 2. What Venus and Earth would look like as seen from Mars.

This may seem like a silly thing to wonder about, since there is obviously nobody up on Mars looking back at us. But here’s the catch: even though there are no people on Mars, there are several robots controlled by people. And those robots have cameras.

Figure 3. Spirit rover picture of Venus and Earth in the Martian twilight.
Picture from here.

Saturday, June 27, 2009

Arctic sea Ice pool: 5 weeks to go

With 5 weeks left to guess, the graph for the 2009 Arctic sea ice minimum gaussian guessing game is looking like this:


Contestants have solid, colored curves. The thick black/grey curves are the Ensemble 1 and 2 outputs from the Wegener Institute’s June 2009 Sea Ice outlook. The collective contestant’s pdf is the dotted light grey line (click to embiggen), and shows a bimodal distribution around the 2007 and 2008 minima. Thusfar only Nick Barnes (4700 ± 200, pink) has been mathematically eliminated at the 2 sigma level. Nick, you can take another guess, if you so desire.

The current value (as of Thursday) is 10,224 thousand km2.

Thursday, June 25, 2009

Proof God exists

Recently, every man and his dog has been yammering on about whether atheists should be fundamentalist dickheads or not. As long-time readers of this blog know, two years ago, when my daughter was barely 2 months old, I left my cozy, stable university technical job for a stint as an exploration geologist.

This meant leaving Mrs. Lemming home on her own for up to a month at a time with a very little child and no-one to turn to. Time has passed, and the chaotic unpredictable-by-science economy has come and gone, causing me to get sacked, rehired in a short term contract, and finally unemployed as of three days from now.

As a result, Mrs. Lemming is going from part time work to breadwinning, and I'm becoming the full-time Dr. Daddy. The timing of this change corresponds perfectly with the Littlest Loveliest Lab Lemming's potty training. And that, my friends, can only be described as Divine justice.

As Divine justice implies a divinity, I can only assume that He or She (probably She, considering the situation) is smiling at one member of the Lemming family and laughing at the other.

Edit: due to transition hecticness, this blog is on autopilot for a little while.

Sunday, June 21, 2009

Minimum Arctic sea ice extent betting pool

Update: 9 days to go

See this page for the current status of this contest.
Posting guesses under that entry will prevent the spam filter from holding your comments.

The previously announced Arctic sea ice extent minimum prediction pool is now open.

Guesses are to be in the form of extent and sigma (a mathematical measure of uncertainty), in thousands of km2 You may use decimal places if you insist.

Your guess will define a Gaussian curve.

The function with the highest value for x=minimum daily measured ice extent (from IARC-JAXA) wins.

Here’s an example graph, for those who are afraid of equations:
The input data are (in thousands of km2):
Colorextentsigma
Black5420300
Red410075
Orange480040
Green4600135
Purple4400100
Blue4500200



For the 2008 minimum extent of 4708 thousand km2, the winner would be green, not orange, due to green’s higher stated uncertainty.

Obviously, the best choice of sigma depends on the number of entrants, among other things. Since I have no way of predicting how many people will enter, there is a second chance rule:

Anyone who is mathematically eliminated at the 2 sigma level will be allowed to guess again. In the graph above, blue would qualify, as they are completely buried in the interval 4100-4900.

The closing date is August 1.

The winner gets to nominate a topic for this blog, which I will attempt to link to mineral sciences in as humorous a manner as possible. Here are some examples.

If you want to tell a bit more about yourself- profession, interest in climate, preferred line color for graph- that would be great. My secret agenda here is to see how the guess distribution varies between climatologists, non climatologist, friend who only want to win to force me to blog about an embarrassing episode in my past, etc. I doubt I'll get enough entries to be able to do that, but if y'all guess and invite some friends along, then we might get somewhere.

So place your bets folks; you have nothing to lose, and I have nothing to gain.

Update: Five weeks to go.

Friday, June 19, 2009

Inner solar system


Here are all the terrestrial planets (incl. moon), visible in the dawn sky from now until the new moon. And because it is the winter solstice, you don't even need to get up early to see them. But you only have a day or two left!

Click to enlarge if you want to see Mercury and Mars.

Thursday, June 18, 2009

Minimum arctic sea ice extent betting pool- ground rules

Attention, anyone more interested in the current climate than that of the paleoproterozoic snowball Earth:
This year, I will be running a betting pool on the 2009 minimum extent of arctic sea ice.

Betting will open on the (arctic) summer solstice, and close at 00:00 of the first of August, UTC.

Betting will probably be of the form value, sigma, as used by Cosmic Variance for the US election last year, but with some added details to be announced on Sunday. Climate statistics nerds, who complain about the inappropriateness of Gaussian curves will have their spokes loosened.

This post is intended to set some ground rules, and ask for advice from those Earth scientists who work in years instead of gigayears. You see, I'm a bit rusty on everything that happened after shells.

So, minimum arctic sea ice extent.
That is extent, not area. Ask a climatologist if you want to know the difference.
I plan on using the lowest daily measurement from the IARC-JAXA satellite webpage (data file). As of yesterday, the extent was: 10,652,813 km2. If there is a better source, please let me know ASAP.

For simplicity, I'll just go with the lowest 'daily' number (probably from sometime in September).

As a prize, the winner gets to nominate the topic of a blog post here at the Lounge.

Any questions, suggestions, or tips?

Wednesday, June 17, 2009

The rebel alliance speaks

Today the Obama administration is starting its human spaceflight review with the first open meeting of the Augustine commission. In short, the successor to the space shuttle program is over budget and behind schedule. In fact, their ready date has slipped four years during the first three years of the program, equating to negative progress.

A few months back, I came across the website of the Direct proposal. This is basically a shadow launch system, designed by NASA engineers in their spare time as their “what we should be doing” project. For a while now, I’ve been applying my crackpot detectors to this, but I’m having trouble detecting anything. They seem to act and think like technical people, not deranged idealists.

Now, one wonders- if their design is better, why isn’t senior management using it? But then, during the last 7 years there were a number of US government departments with ineffective administration. Seen in this light, the current boondoggle is not terribly surprising.

The hopeful development is that the Direct team has been granted a 30 minute presentation at the Augustine commission hearing today. Whether anything further develops is something I can’t predict, but at least senior government people are now listening to alternative solutions instead of blindly staying the course and squashing dissent. I’m optimistically hopeful that America will get back to the moon before I turn 50. Since the last man left before I was born, I’d kinda like the opportunity to see someone new have a crack at that field locale.

After all, the rocks are Da Bomb.

Saturday, June 13, 2009

What do you mean, “if”?

Lockwood, our accretionary wedge compiler for this month, wants to know what I would do if I had a time machine. What is this “if” business? I work in a SHRIMP lab, and the SHRIMP is a time machine. For the past 5 months I’ve been commuting to the early Proterozoic to see how one of Australia’s major ore-bearing tectonic regions was assembled.

So, there’s no *If* about it. I time travel every day. The thing is, so do most geologists. That’s what we do. Geology is a type of investigative reporting where we piece together stories from hundreds of millions of years ago by extracting eyewitness accounts from whichever rocks happened to be witness to the events that interest us. Being a dastardly sort of geologists, I simply do this by torture. I stick the rocks in a steel chamber, suck the air out, and then blast them with an ion beam until they talk.

So, a more appropriate question is, where do I take my time machine, and for that question, I give you this: A probability density diagram for my geochronological career. Note that my current project is embargoed, and thus is not represented. Expect the period 1500-2100 to fill up one it becomes available.

Figure 1. A probability density diagram of all my geochronology.

* This is like one of those placeholder abstracts you see at big meetings, only even more blatant. A big slab of the data I want to plot is not actually available- I’ve been working on the paper at work at nights and on weekends, and only have the raw data at home, which I can’t be bothered reducing all over again just for blogular expediency. So I’m slide the figure in whenever I get a chance sometime in the next few days.

Friday, June 12, 2009

What’s my fuel efficiency?

People are finally realizing that we are disrupting the climactic conditions that allowed our species to evolve from hunter gatherers to sophisticated agricultural societies. As a result, there is increasing interest in regulating carbon dioxide. CO2 emissions are quite complex and indirect in some cases, but automotive transport should be one of the easier places to measure carbon emission, use, and efficiency. For example, many newer cars come with dashboard display units that tell you what your fuel efficiency is. Or so we are led to believe.

A year and a half ago, I blogged on the fuel efficiency of my old motorcycle, which was comparable to Jim and Callan’s Priuses. This autumn, I started tracking the fuel efficiency of our family car, a small turbodiesel European wagon. I did this the same way I did for the bike- dividing the fuel purchased by the distance driven to get the liters per 100 kilometers- the standard efficiency measure for metric driving.

As I was doing this, I started to notice that the numbers I was calculating did not agree with the dashboard display. While the fuel use method is known to be imprecise (it is hard to fill the tank to exactly the same level every time), it should be accurate over the long term. So I started recording both numbers. And after half a dozen refills, I have the following data:

Derivation methodmeansigma
Calculated l/100k6.30.5
Reported l/100k5.60.1



Figure 1. Blue line is calculated efficiency, Pink line is values reported on dashboard computer.


Figure 2. Same data, converted into miles per gallon for the sake of unscientific Americans

With an average of 800 km between refills, the average fuel difference is about 5.5 liters per refill, or about 11%.

I checked the computer distance traveled against the odometer- the numbers are the same. The six refills came from four different service stations operated by two different companies (Shell and BP). No obvious difference. At this point, my working hypothesis is that the computer underestimates its fuel use, but I’m open to suggestions for how to test this hypothesis. In the mean time, if anyone else out there want's to check a different car model, it would be interesting to see what y'all come up with.

Wednesday, June 10, 2009

One step at a time

It seems like a lifetime ago, but 16 years before today I climbed up a foggy rainy mountain in central Maine before starting a five month amble through the Appalachian summer into the crisp fall of Georgia.

As the time, I was burned out from two years of college, and sick of the Yankee smugness, the city lights, and the self importance of university. So I walked away. I’ve always been partial to trees, and surrounding myself with nothing else for half a year seemed like a perfect cure. And yet…


There was something aside from trees out there. The trees grew in dirt, and poking up through the dirt I saw rocks.

Flipping back though my photos, I was pleasantly surprised at how many of them show metapelites. What started as a slate belt developed quartz veins, then folds, then micas, and eventually garnet and staurolite in the month it took me to get into the big hills of New Hampshire. And I realized that if I ever really wanted to understand the stories that these rocks were trying to tell me, I’d have to go back to the dirty streets and crowded halls of college. The same campus that harbored self-important druggies and screechy activists also had microscopes and libraries. And the more I learned about rocks, the farther I could go to visit them.

A year later I was in the wild West, learning field mapping in the first half of the summer and hitch-hiking between geologic hot spots in the second half. Three years after that I was in Australia, and by the turn of the century I’d been to five continents.

Sixteen years on, I’m not really sure where the next step leads. I’ve run out of little white rectangles to follow. But I’d be surprised if it didn’t involve rock of some kind.

Tuesday, June 09, 2009

Stop Rape

Sexual assault is wrong. There is no clever angle to take, no mathematical metaphor to propose, no stunning desert photographs to illustrate it. So there isn’t much I can add to the growing internet chorus against it.

Sheril Kirshenbaum has launched a cyber-attack on sexual assault. Focusing on aid to conflict-ravaged African countries where rape persists, she’s gotten an impressive number of people to donate their revenue to the cause.

I don’t have much to add here. This blog is ad free, so donating my income from it is a meaningless gesture. And I don’t have much silence to break; although I did my PhD in a research group in which male students and technicians were harassed, I escaped with nothing more serious than getting my ass grabbed.

But I would like to point something out for any geology students interested in economic geology and social justice: When a conflict ends, resource companies are often the first large companies back on the ground in war-torn third world countries. A woman I studied with has worked in several of the countries highlighted in Kristof's article. The degree to which companies invest in the social fabric of the countries in which they operate is highly variable. But for those of you who want to make a concrete and positive impact on war torn African countries, exploration geology is one way to get into their economies.

There is more to life than post-docs.

Médecins Sans Frontières- Australia
Donate

Billions and billions of space blogs

Here. (Note a 7-8 order of magnitude hyperbole)

Monday, June 08, 2009

Australian science history and culture

One of the more impressive accomplishments of Australian geoanalytical science is the invention of the SHRIMP mass spectrometer.

The SHRIMP, or Sensitive High Resolution Ion MicroProbe, is the first instrument that can directly determine the age of a mineral in situ; before SHRIMP, the only way to measure radiogenic ages was to dissolve the target mineral, chemically separate the parent and daughter products, and measure them independently.

Back when the SHRIMP was first built, in the early 80’s, it was very loud. The SHRIMP avoids chemical interferences in its lead measurements by achieving mass resolution so high that the binding energy of the nuclei separates lead from molecules with the same nominal mass. It does this by having a very large radius magnet. This, in turn, results in a large instrument, which has a large volume, all of which needs to be kept under vacuum. The high vacuum is maintained with turbo pumps. Modern turbo pumps are barely noticeable, but the early ones used in the 80’s were very loud.

Also, the SHRIMP was built in a room directly under the library. As a result, it was sound-proofed, as is shown below.


Figure 1. The SHRIMP lab, with aging sound-proof tiles.

Technological advancements mean that this soundproofing has become superfluous as the pumps have become quieter. As a result, it is not maintained. 30 years of vacuum oil have slowly colored the white foam tiles brown, and the foam has begun to fall apart. As the foam is less durable than the glue that was used to hold it to the walls and ceiling, when the tiles eventually come off, they leave glue marks where they were attached (fig 1.).

This is interesting, because by analyzing these gluemarks, we can deduce that the people who installed these tiles grew weary of the task during installation. Before proceeding, however, you need to realize that this is the crown jewel of Australian geoanalytical science. For 10 years, it was the only machine in the world that could do what it does, and it revolutionized the study of complex, multiply metamorphosed terrains that make up the bulk of the early earth rock record. Scientists from all over the world come to see it. Which is what makes the following all the more amusing.


Figure 2. Geochronology allows us to decode messages from the past.

In a tightwad culture, this would be a scandal; a disgrace. Here, though, it’s revered history. Australian for classy.

Sunday, June 07, 2009

Women scientists from outer space

There are some new carnival notifications in my inbox. As far as I can tell, women scientists from outer space have landed here on earth with the intention of kidnapping our innocent green-skinned, oval-eyed bipeds to slake their extraterrestrial lust. Or, I may have been reading too much gender-reversed sci-fi pulp.

Thursday, June 04, 2009

The Lake Eyre basin

The Lake Eyre basin is Australia’s largest drainage system, and the 4th largest Endorheic drainage in the world. The main northern Rivers, the Diamantina and Georgina rivers, Are fed by the summer monsoons. These rivers discharge into a large deltaic/swampy region of interconnected channels and lakes known as the Diamantina, and channel country, which in turn drain into Lake Eyre. The farther downstream you go, the less likely it is that flooding occurs. So while the northern rivers have flow during most summer monsoons, the Diamantina only gets a decent soaking every few years, and Lake Eyre itself only fills a few times per century. As a result of heavy rain this January, the lake is currently close to full and still filling, as seen in this satellite image from NASA’s Earth observatory:


Prior to this event, I was doing exploration in part of channel country that was filled by a rare local winter storm a few months before our expedition. The waterfowl were fairly impressive for a region that is sand dunes and salt flats for most of the time. Here are some brolgas:


hat tip: Brian

Tuesday, June 02, 2009

DIY nuclear experiments

People might get the false impression from this blog that I underestimate the risk of ionizing radiation. That is not the case. Radiation is dangerous. It is also well understood, and ubiquitous. A natural 400 KeV gamma ray will do just as much damage as a natural one, so treating the risks from them differently doesn’t make a whole lot of scientific sense.

That being said, one needs to respect nuclear materials. If you are going to build a nuclear reactor in your garden shed, there is a right way and a wrong way to go about it. The first half of the 20th century is full of tales of radiation-induced sickness that happened because people didn’t know what the risks were. We know now. So educate yourself, and be sensible of you are going to fool around.

Monday, June 01, 2009

Is need-based hiring good for women?

A while ago I was looking at a job opening in one of the world’s best geochemistry labs. Asking people in the know, I got the following advice:
“If you’re gonna apply, do it fast. They don’t hold a traditional search, they just take the first qualified applicant.”

I was taken aback by this, but I don’t know why. After all, this is how positions in the real world are filled. A job needs to be done, so when someone who can do it shows up, they’re hired. A job is not a gift to be bestowed on the winner of a competition; It is something that has to be done. And in the case of this particular lab, the approach obviously works well for them. They are the best at what they do. So I started wondering: Why isn’t this approach used more often. And I wondered some more: Would such an approach help bridge the gender gap?

Pondering the last question, I think that it depends on the cause of the gap. Let’s assume two endmember causes for underrepresentation of female hiring at high levels in academia. The first endmember assumes that everybody in the selection processes that produce male bias is slightly biased against women. The second assumes that a small number of selectors are strongly biased*.

If the second case holds true, then those institutions saddled with such a person will always find an excuse not to hire women no matter what, so the search methodology is irrelevant.

With the first case, if you have a bunch of almost equal people competing for a spot, then subtle biases could end up making the difference that gives the job to a male. But if they simply hire the first qualified person to come along, then that subtle difference shouldn’t matter, as long as the advertising process is open and honest. Obviously, that’s a big if- a first come first serve practice could easily be corrupted by an old boys network**.

On the practical side, A first qualified candidate will generally enhance the productivity of the selectors, as the service commitment would generally be smaller. And if it works faster, it would be more amenable to researchers who have a family to support and can’t wait around for 15 months while a process slowly churns. But I honestly don’t know what the gender breakdown for scientist heads of households is, so I can’t say if that’s gender related or not.

* Note that overt bias is illegal and/or socially unacceptable in a growing number of countries these days. So the sort of person I’m talking about here is someone who claims to be fair-minded in principle, but always finds a reason to disqualify any specific woman who interacts with his sphere of influence. Whether this is done consciously or unconsciously is irrelevant for the present argument.

** Assuming that most labs are run by old boys- otherwise, it could be corrupted by the Nefarious Web of Quazinonymous Women Bloggers in the opposite direction.