Tuesday, August 31, 2010

Mohs Scale of Hardness

When teaching students how to identify minerals in introductory geology labs, we have them look at the physical properties of the minerals.  Things like color, hardness, cleavage (how it breaks), crystal form, etc.

Hardness is one of the more distinctive properties that minerals possess and relatively easy to determine.  Every mineral is assigned a hardness number between 1.0 and 10.0.  This scale was designed by the German mineralogist Frederich Mohs (1773-1839) in 1812 and is therefore known as Mohs Scale.  What Mohs did was to assign a common representative mineral to each whole number with 1 being the softest known mineral and 10 being the hardest.

1 - Talc (softest)
2 - Gypsum
3 - Calcite
4 - Fluorite
5 - Apatite
6 - Orthoclase
7 - Quartz
8 - Topaz
9 - Corundum
10 - Diamond (hardest)

Generations of geology students have been tortured by evil professors who make them memorize Mohs Scale minerals and there are a number of mnemonics that have been devised over the years.  The one told to us by my mineralogy professor many years ago was "Texas Girls Can Fuck And Other Queer Things Can Do."  In these more politically correct days, I tell my students "The Girls/Guys Can Flirt And Other Queer Things Can Do."  I've even seen "The Geologist Can Find An Ordinary Quartz Tourists Call Diamond" and "Two Giddy Chickens Found A Friendly Quiet Turtle Cooking Dinner."  Hey, whatever works - sometimes the most obscene mnemonics are the ones you'll remember 30 years later!

While you can puchase hardness testing tools, the easiest way is to simply amass a collection of 9 small mineral samples representing the hardnesses above (our geology lab testing kits do not have diamonds in them for obvious reasons!).

Usually these kits also include a piece of glass (H=5.5 on Mohs Scale) and a piece of copper (H=3.5).  Other objects you can use to test hardness are a penny (H≈3.5), a steel file (H≈6.5), or your fingernail (H=2.5) - female students with manicured nails are sometimes reluctant to go around scratching minerals however.

So, the procedure I usually give my students is to first try to scratch the glass plate with the mineral.  If it scratches the glass it's harder than 5.5 or so and if it doesn't it's less.  If it's less, I would then test it with my fingernail.  Then the copper strip or penny.  Then I would go to the mineral hardness kit to narrow it down.  For many minerals in the introductory geology lab, testing with a fingernail and glass plate is usually all you need to narrow it down.

Hardness testing is often useful in the field as well.  Veins (mineral-filled fractures) like those below are commonly either calcite (CaCO3) or quartz (SiO2) - two very different minerals that can look very similar at times (especially for students).

A quick test with a knife blade, however, will easily reveal which mineral it is (geologists are typically always armed with a knife).  Calcite has a hardness of 3, quartz has a hardness of 7, and a knife blade is typically around 5.5-6.  If it scratches easily with the knife, it's calcite.  There are a number of common minerals that may look similar but are easily distinguished by their hardness.

One interesting thing about Mohs Scale is that it's not linear.  In other words, the difference in hardness between 4 and 5, for example, is not the same as the difference in hardness between 8 and 9.  Diamond, at 10, is actually off the chart!

This really doesn't matter too much since we're not testing many diamonds in my lab!

What are we actually testing when we look at a mineral's hardness?  Hardness is actually related to a number of things in minerals.  The size of the atoms comprising the mineral, their bond lengths, and the type of bonds (e.g. covalent, ionic, van der Waals) all plays a role.  What we're really testing is resistance to abrasion since we're scratching the minerals to determine their hardness.  Here's a good short article on the topic.

Monday, August 30, 2010

Hmmm, beer.

Study after study has shown the moderate alcohol consumption is actually good for you.  One recent study showed that drinkers, even heavy drinkers, have longer lifespans than teetotalers (that's actually surprising!).

Beer consumption is nothing new for geologists, we're known for it.  Back when I was in school, no field trip was complete without the evening beer run and we regularly drank at our department colloquia on Friday afternoons (arranging refreshments was an official Teaching Assistant duty).

My only problem is that I like good, full-bodied beers - none of that "Lite" swill that passes for beer - and those beers have a lot of calories.

Many of my most interesting geology discussions were not in the classroom but over a couple of beers in a local bar.  I miss those days.

Sunday, August 29, 2010

Calculators in the classroom - revisited

About a month ago, I had a post called "Damn faculty, standing in the way of student success..." where I disagreed with a post on Calculators from Dean Dad's Confessions of a Community College Dean blog.  Interesting post today on the snarky College Misery blog titled There are no stupid questions...Or are there? with another example of where rampant calculator use among K-12 students has resulted in clueless college students.  It's a simple question, do we want a nation of button pushers for whom math is magic or do we want college graduates who can think?

Saturday, August 28, 2010

Pretty Picture

No time to write up anything today.  Visiting family in Maryland.  Here's a picture of a butterfly on a zinnea from the front of our house a week or so ago.

Friday, August 27, 2010

Bug juice

My kids like SoBe Lifewater which we'll sometimes get them if we're driving around somewhere and end up getting drinks and snacks out of a convenience store.  It's not really good for them since a quick look at the ingredients list shows that it's basically flavored sugar water.

Ingredients: Filtered Water, Sugar, Erythritol, Natural Flavor, Monopotassium Phosphate, Citric Acid, Ascorbic Acid (Vitamin C), Potassium Citrate, Calcium Lactate, Modified Food Starch, Cochineal Extract (Color), Taurine, Vitamin E Acetate, Calcium Phosphate, Gum Arabic, Panax Ginseng Root Extract, Calcium Pantothenate, Niacinamide, Elderberry Juice Concentrate (Color), Pyridoxine Hydrochloride (Vitamin B6), Cyanocobalamin (Vitamin B12). Filtered Water, Sugar, Erythritol, Natural Flavor, Monopotassium Phosphate, Citric Acid, Ascorbic Acid (Vitamin C), Potassium Citrate, Calcium Lactate, Modified Food Starch, Cochineal Extract (Color), Taurine, Vitamin E Acetate, Calcium Phosphate, Gum Arabic, Panax Ginseng Root Extract, Calcium Pantothenate, Niacinamide, Elderberry Juice Concentrate (Color), Pyridoxine Hydrochloride (Vitamin B6), Cyanocobalamin (Vitamin B12).

Anyway, we were reading the ingredients list once (we try to get the kids to pay attention to such things) and noticed cochineal extract.  I told them that it came from bugs but no one believed me.

Cochineal bugs (Dactylopius coccus) are parasitic scale insects that live on Mexican to South American cacti.  They produce a chemical called carminic acid (C22H20O13) which deters predators and from which you can obtain a crimson-red dye.  This dye has been in use since the time of the Aztecs.  It's use waned in the 20th century with the use of synthetic red dyes but many of these artificial dyes were found to be carcinogenic (like the infamous red dye #2) so cochineal use has picked up in recent decades.  The dye goes by many names including "cochineal extract", "carmine", "crimson lake", "natural red 4", "C.I. 75470", "E120", and "natural colouring".

To make the dye, the insects are manually collected from the cacti (very labor intensive), dropped in boiling water to kill them and then dried.  After drying out, they are crushed into a powder and boiled with sodium carbonate (Na2CO3) or other chemicals (sodium carbonate is naturally occuring in some some alkaline "soda" lakes).  It supposedly takes some 70,000 insects to yield one pound of dye.

Cochineal bugs on a cactus pad (they exude a white waxy substance)

Knowing that cochineal extract comes from insects hasn't deterred my kids from drinking Lifewater but they do refer to it as "bug juice" now.

Thursday, August 26, 2010

Strange solar systems

Researchers recently announced the discovery of an extrasolar system (a solar system around a star other than our Sun) with at least five, and maybe seven, planets.  The star is HD-10180 located in the constellation of Hydrus (a Southern Hemisphere constellation) about 127 light-years (750,000,000,000,000 miles) away.

Researchers used the European Southern Observatory in La Silla, Chile and an instrument known as HARPS - the High Accuracy Radial velocity Planet Searcher - a spectrograph that can detect extremely minute "wobbles" in stars caused by the gravitational attraction of orbiting planets (just one of several different techniques currently used to search for exoplanets).

The wobble of this star was complex and some advanced computer processing was required to determine that the motion could be explained by 5 Neptune-sized planets orbiting closer to HD-10180 than Mars orbits to our Sun.  (Just to be clear, while we have directly imaged some exoplanets, others, like these, are indirectly inferred from their effects on the parent star).  There's also the possibility of another Saturn-sized planet close in to the star as well as a planet 1.4 times the size of the Earth (would be the least massive explanet found if confirmed) orbiting the star every 1.18 Earth days!

In the past decade, sophisticated astronomical instruments have allowed us to detect hundreds of exoplanets through a variety of techniques.  So far, these exoplanets have been large gas-giant types (like our Jupiter, Saturn, Uranus, and Neptune) since it's easier to detect large exoplanets.  Small rocky planets like our Mercury, Venus, Earth, and Mars are what most astronomers really want to get at because that's where we're most likely to find life.  One of the things we've seen, however, is that most of these other solar systems are really strange places compared to our own.  It may be that our solar system, with its nice arrangement of 4 terrestrial planets and 4 gas-giant planets, with the Earth in a nice zone for liquid water, may be an aberration.  But, who knows, the universe is a big place!

Artist's conception of an extrasolar planet from Astronomy Picture of the Day

Wednesday, August 25, 2010

New age for the Solar System

A meteorite now known as Northwest Africa (NWA) 2364 was discovered in the Sahara Desert near Erfoud, Morocco around 2004 and recently studied.

NWA 2364. Image © T. E. Bunch, 2004

This meteorite is classified as a CV3 - a type of meteorite known as a carbonaceous chondrite (the chondrules are the spherical inclusions dotting the meteorite and are formed from once-molten material).  Carbonaceous chondrites are thought to represent the oldest meteorites in the solar system and actually have a chemical composition similar to that found in the photosphere of the sun.  CV3 chondrites give us information about the composition and evolution of the early solar system.

CV3 type meteorites also have large calcium-aluminum-rich inclusions (CAIs) typically composed of minerals like anorthite feldspar (CaAl2Si2O8) among others.  These types of inclusions can be radioactively dated with uranium-lead (U-Pb) isotopes.

A recent paper in Nature Geoscience presents results indicating that this meteorite is 4,568.2 million years old.  That's 4.568 billion years which pushes it back another few hundred thousand years (nothing dramatic, just a refinement of what we already suspected).

So, while I used to tell students the solar system was 4.56 Ga (Ga = giga-annum or billlion or 1,000,000,000 years), now I'll tell them it's likely 4.57 Ga (rounded off).

Tuesday, August 24, 2010


Burdock (Arctium spp.) denotes a group of non-native thistles found throughout the Hudson Valley and now in flower.  Here is a picture of this familiar plant from the North-South Lake DEC campground in the Catskills.  It's easy to identify from the large leaves and sticky burrs.

The flowers, in the center of the burrs, were being actively visited by ants and bees.

My kids and their cousins had a good time picking burrs and throwing them at each other!

Since it's so common and unmistakable, burdock is a good plant to know in a survival situation.  The burdock taproot can be dug up, cleaned, and boiled for use as a vegetable.  Burdock root is actually popular in Japan where it's called gobo and used in a number of traditional dishes.  In England, fermented dandelion and burdock roots have been made into a drink since 1265 (I want to try this sometime).

As with most edible wild plants, burdock also has had medicinal uses.  Oil extracted from burdock roots, called "bur oil" in Europe, has been used as a scalp treatment to help fight hair loss.  Burdock leaves (immature leaves are also reputed to be edible) have been made into poultices for burns.

Look closely at the burrs next time you see a burdock plant.  See the little hooks? 

The story goes that in the 1940s, Swiss engineer and inventor George de Mestral was out hunting with his dog when they encountered some burdock (dogs running through burdock come back covered with burrs).

You or I would have just bitched about this plant and cursed the stupid dog but de Metral was curious - he examined the burrs under a microscope and saw hundreds of little hooks which would catch on loops of fiber and animal hairs.  Then he invented Velcro, spent years perfecting the process, and made millions.  That's the difference between successful inventors and people like us!

Monday, August 23, 2010

ISS Passes

Want to see the International Space Station (ISS) passing overhead this week?  It's well situated for viewing here in the Northeast after sunset and quite bright.  The reason we can see it is because it has a lot of flat metal surfaces which reflect sunlight.  While it's dark here on the ground, it's 20 miles up and can still reflect sunlight from the Sun which is below our horizon.

Here's a data table of pass times for Kingston, NY in the heart of the Hudson Valley.  If you want this data for your town, visit Heavens-Above.com and select your location.

How do your read this?  Well, the first column is obviously the date and the Time colums are the local time in EDT (24-hour format).  Starts is when the ISS first appears in the sky, Max. altitude is when it hits its maximum altitude, and Ends is when it disappears.

The second column, Mag, is the magnitude or how bright the object appears.  It's a hold over for the ancient Greek astronomer Hipparchus who said the brightest stars had a magnitude of 1 and less bright stars had magnitudes of 2, 3, 4, 5, or 6 with 6 being the dimmest he could barely see.  Today, this logarithmic scale is defined a bit more precisely, and includes negative numbers, with the brightest star in the sky, Sirius, being a magnitude -1.5.  Bottom line is that lower numbers refer to brighter objects. For example, the ISS will be brightest on the first pass of August 26 with a magnitude of -3.5.  The dimmest pass will be the second one on August 27 with a magnitude of -0.1 (still brighter than all the stars of the Big Dipper).

Alt. and Az. refer to the position of the ISS in the sky at the indicated times.  Altitude is the angular height above the horizon.  An object directly on the horizon has an altitude of 0°.  An object directly over your head (at the zenith) has an altitude of 90°.  There's an easy way to estimate altitude.  Hold your fist out at arm's length and it covers about 10° of the sky.

Azimuth is simply, in this case, the compass direction where the ISS will appear.  For example WSW is half-way between west and southwest.  If you know how to find the North Star, it's easy to figure out where to look (I should post on this sometime).

So, if it's clear Thursday night, for example, go outside around twenty after eight and look for a very bright light moving across the sky from the SW horizon, to half-way up the sky in the SE, and then disappearing in the ENE.

Yeah, right...

In December, the community college where I work had a $219,141 reduction in funding from New York State that was applied in the middle of our academic year (our budget year runs from September 1).

For 2010-2011 Governor Patterson's budget will result in a $954,015 reduction in our operating budget - that's a 16.6% reduction in our funding from New York State [numbers are from a letter recently sent out by our college president].

Found out last week that TAP - New York State's Tuition Assistance Program (financial aid) - will go down by $75 a year at a time when all colleges have been forced to raise their tuition.

Community colleges often serve those students who would not be able to attend a traditional four-year school.  We serve underprepared students, place-bound students, adult students returning to school, etc.  We're open admissions - everyone is given a chance to attend and succeed.  If they can afford it.

So, when the New York State governor or state legislators talk about how much they value higher education in New York State, feel free to tell them they're full of shit.

Sunday, August 22, 2010

Water, nope. Food, nope. Cellphone, check

The stupidity of people never ceases to amaze and astound me.

Read about clueless visitors to national parks in this recent New York Times article.

Jack Horkheimer (1938-2010)

An astronomical icon passed away on August 20 - Jack Horkheimer, the Star Gazer.  He was director of the Miami Planetarium and had a syndicated weekly astronomy program on PBS since 1976. 

A bit of trivia - the show was originally called Star Hustler but was changed to Star Gazer in 1997 because, in the age of the Internet, search engines like Google prominently returned links to Hustler magazine when kids were searching for Star Hustler!

Horkheimer would always open his five-minute show with "Greetings, greetings fellow star gazers" and signed off with "Keep looking up."  He would discuss what was interesting and visible in the sky that week.  Despite his generally goofy demeanor and cheesy sets, his enthusiasm for astronomy undoubtably influenced generations of kids into developing an interest in the night sky.

Click to view one of his last programs.

Phil Plait's Bad Universe

Phil Plait's Bad Universe debuts next Sunday, August 29, at 10 pm (ET) on the Discovery Channel. 

While suffering from the "science isn't interesting unless there are explosions syndrome", and looks a lot like MythBusters, at least it's an astronomy program starring someone with a PhD in astronomy!  I saw a lecture by Plait recently and he's very entertaining and should do a great job.

Saturday, August 21, 2010

I'm not crazy

Because I take walks in the woods, I don't need to see a therapist.  That's my story and I'm sticking with it.

Read about ecopsychology.

Aurora from space

Sunlit on the Earth's surface, but up in the International Space Station, NASA astronaut Doug Wheelock viewed an aurora on August 13 when a minor stream of solar particles hit the ionosphere.

Click image to enlarge.  Amazing view.

Friday, August 20, 2010

My new home

Here is the cave where I want to live.

When people below annoy me, I will pelt them with rocks.

Inspirational Quotation

"The lesson which life repeats and constantly enforces is, "Look under foot." You are always nearer the divine and the true sources of your power than you think. The lure of the distant and the difficult is deceptive. The great opportunity is where you are. Do not despise your own place and hour. Every place is under the stars, every place is the centre of the world."

The Divine Soil (1908)
John Burroughs

John Burroughs (1837-1921) was a naturalist who spent much of his life in the Catskills and Hudson Valley region of New York.  Living here in the Hudson Valley, I sometimes pine for the mountains and deserts I love to visit out west.  I need to be reminded that there's beauty and grandeur wherever you look - you just need to seek it out and be open to experiencing it.

Thursday, August 19, 2010


Just got a phone call in my office today from a women asking for someone who "knew about UFOs."  I could tell she was up for a long conversation and whatever I said would be evidence of my closed-mindedness.

I'm very evil... I told her no one here was an expert on the subject (technically true) and suggested she call the SUNY New Paltz astronomy department!

I've got enough work to do today.

Misunderstanding the equal sign

Interesting blog post at Cocktail Party Physics on student's misconceptions about how the equal sign (=) works.  If you teach math or science, you should go read it - I found it surprising.  Like the author, I've always thought of the equal sign as a see-saw as well - one that's inviolable.   Turns out many kids have a different view, seeing it in a much more limited way (generally as the "enter" key on a calculator).

Wednesday, August 18, 2010

Natural Cement lecture on Friday

I'm giving a talk on the "“Geology and the Rosendale Natural Cement Industry” Friday evening, starting at 7:30 pm, at the Mid-Hudson Gem & Mineral Society meeting in Poughkeepsie.   It's free and open to the general public.  The location is at the Mill Street Loft, 46 Pershing Avenue, Poughkeepsie.

This local industry once produced more than half of the natural cement used in the United States!  Come and learn how ancient subtropical seas and massive Himalayan-scale mountains once existed here in New York and helped form this once-important economic resource that still has an effect on our local ecosystem.

Old room-and-pillar cement mine near Binnewater, NY

Bank of cement kilns near Williams Lake, Binnewater, NY

Tuesday, August 17, 2010

Chatter marks

Beautiful chatter marks, striations, and glaical polishing in Shawangunk Conglomerate near Lake Minnewaska  (Swiss army knife for scale).

These glacial features aren't caused by the ice moving over the rocks - you can take an ice cube and rub it on a rock all day and it's not going to affect it (especially a rock made entirely of the hard mineral quartz as the Shawangunk Conglomerate is).  These features are formed from rocks and sediment carried in the ice making it abrasive - just like sandpaper moving 24/7 for thousands of years!

Chatter marks are crescent-shaped chips in the bedrock indicating the direction of glacial movement (away from the camera here).  As glaciers move, they pluck up rocks which get embedded in the base of the ice.  These rocks then "skip" across the bedrock chipping out the marks.  Striations are the fine parallel lines formed by subglacial rocks scratching the bedrock as the glacier moves and glacial polishing is from sediment embedded in the base of the glacier acting like sandpaper.

These kinds of features (and others) were noticed for what they were by the brilliant Swiss geologist/paleontologist Louis Agassiz (1807-1883) who studied glaciers and glacial features in the Alps and then saw these exact same erosional and depositional features throughout Europe and later in North America (he taught at Harvard).  Agassiz proposed a great Ice Age as the explanation for these features.

Any keen observer in the Hudson Valley will notice dozens of different lines of evidence indicating that this area was once covered by a great expanse of glacial ice.  This outcrop (and thousands of others just like it in the Shawangunks, is just one example).  As time goes on, I'll post others.

Monday, August 16, 2010

Open admissions

Interesting article at Education Week (August 13) titled Community Colleges Rethink 'Open Door' Admissions as Remedial Costs Rise

Chicago mayor Richard Daley Chicago Mayor Richard Daley this week called for an end to the "open door" admissions policy at Chicago City Colleges, citing concerns about the cost of remedial courses and a desire to build a quality program.

This is a HUGE problem around the country.  Community colleges (CCs), such as the one I work at, have open door admissions.  Show up, pay the tuition in some way (typically via financial aid), and take classes.

Well, almost.  At our institution, and all other CCs I'm sure, students are first given math and English placement exams.  A significant proportion (majority) of incoming students will require either remedial English (i.e. they can't write a coherent paragraph) or math (i.e they can't solve simple algebraic equations).  A portion of our operating budget therefore goes toward offering large numbers of sections of remedial English and math classes.  Did I mention that many of the students placing in remedial English and math this fall semester graduated from a local high school with a diploma last June?  Don't even get me started on that!

Compounding this is the fact that during hard economic times, enrollment at CCs rise.  We're cheaper than four-year schools (students can live at home too) and people who've lost jobs will often think about returning to school to retrain for another field.  Unfortunately, support from the amazingly inept State of New York has gone down as enrollment goes up (1/3 of our budget)!  Support from the local county has remained flat (another 1/3 of our budget).  Tuition went up slightly (the final 1/3).  We're trying to educate more students but with less money (quite the business model - when enrollment increases, our financial situation gets worse!).

So, with enrollments up, we have to offer more remedial education classes.  Here's another problem.  A student's financial aid will only pay for so many semesters (typically 3 years to get a 2 year CC degree).  One scenario that often occurs is that a student places into a remedial writing class and a remedial math class.  Guess what, students who can't write also typically never read books either (that's why they can't even recognize that their writing sucks).  That's 6.0 credit hours and they need two other courses to get up to 12.0 credit hours.  Not remedial courses, but college-level courses because that's what financial aid rules require.  THIS STUDENT CAN'T READ, WRITE, OR DO MATH, WHAT THE HELL COLLEGE-LEVEL COURSES DO THEY WANT US TO PUT HIM INTO!!!  Did I mention some students need two or more semesters of remedial courses to get up to college level (often more than two semester's worth in math)?

Then to top it off, the administration then holds meetings to come up with strategies to increase retention because all these remedial students can't handle college-level work and end up flunking out or, more commonly, simply disappearing.  What a fucking surprise!  We then set up these systems such that we have to send alerts when students aren't coming to class so that someone can call the student at home and ask why he's not dragging his ass to class anymore.  Faculty, especially the increasing number of adjunct faculty we have, then start getting worried that they'll be accused of harming retention if they fail too many students.  Academic standards inevitably go down.

In the article, George Boggs, president and chief executive officer of the American Association of Community Colleges, says:

I'm a little concerned about this," Boggs says. "Community college has always been an open door for college. We have taken everybody." Students are assessed upon entry and take remedial programs if they aren't prepared. Boggs doesn't want to see colleges weed out students who are least able and don't have many other options.

It's like a hospital that only sees healthy patients, Boggs says. "I hate to see that philosophy—to improve quality by denying access to the most at-risk students," he says. "Where are these students going to turn? We need to find some way to take care of these students. We can't just leave them out there. It hampers their ability to be contributing members of society."

It's a noble sentiment but assumes that everyone can do college-level work.  I am a firm believer in giving everyone a chance to come to college and succeed but if you can't handle the material, find something else to do.  College is not for everyone.  Perhaps that makes me an elitist but there it is.  The end result of the above noble but naive philosophy is that a college degree will soon be worthless - much like a high school diploma is today.  Colleges should not be forced, especially without any financial support, to re-teach students material they should have learned in high school.  This is a public school problem, it shouldn't be a CC problem.

Sunday, August 15, 2010

Scarlet tanager

Slightly blurry picture of a scarlet tanager (Piranga olivacea) seen while hiking near Lake Minnewaska recently.  Hard for my digital camera to focus on the bird through all the intervening vegetation.

First time I've seen this beautiful bird out in the wild in this area.  These birds are hard to spot since they're shy and spend a lot of time in the forest canopy making them difficult to see.  They have a nice song (sometimes compared to that of a "robin with a sore throat") but I'm not sure I could recognize it in the woods.

Unbelievably, this little bird migrates to and from South America every October and April where it overwinters in places like Columbia, Ecuador, and Peru.  Unfortunately, scarlet tanager populations are declining in the Hudson Valley, most likely from habitat destruction due to ever-increasing development in the area.

Saturday, August 14, 2010

How to piss off your professor

Or anyone else, for that matter...

Came in special the other morning, just for a student who's been procrastinating on getting registered for the fall semester.  He should have done this last April but nevermind.  Makes my job harder because many classes are now closed and I have to check enrollments for everything.  He wanders in 45 minutes late for his appointment totally unprepared.  No "I'm sorry" or anything.

Those of you who are in academia probably aren't surprised by this.  Talking to my colleagues, it's very common for students to make appointments and then wander in extremely late or never show without an explanation or apology.  It's also common for many students to show up completely clueless about what they need to take and completely apathetic about their education (then you look at their transcripts and see all the Ds and Fs).

Sometimes I just want to ask them "Dude, what the hell are you even doing here?"

But we can't because we want their money.  (Oh I'm sorry, did I say that out loud?)

Anyway, you would think it's not a good idea to piss off your academic advisor or professor.  Someone you come to for assistance, accomodations, and recommendations.  I'll never understand it because I'm one of those people who shows up early for everything and get high blood pressure if I'm 2 minutes late for an appointment.

Don't get me wrong, the vast majority of faculty at my institution, including myself, love it when students are motivated and interested in our field.  We will go out of our way to assist them (like come in early some fine summer morning to register their lazy asses).  But don't waste my time.  Unlike these slackers, I have better things to do most days.

Friday, August 13, 2010

Stone-age dildo?

Got your attention, didn't I?

There were a few stories about this find back in mid-July but I didn't get a chance to read more about it until now.  Archaeologists excavating waterlogged river sediments near Motala in Östergötland, Sweden have been unearthing mesolithic bone and wood artifacts which are rarely preserved elsewhere (organic material typically rots away unless it's sealed off from oxygen).

A few weeks ago, the following object was found making news headlines around the world (Stone Age Carving May be Ancient Sex Toy, Stone Age Carving: Ancient Dildo?, and Stone Age Discovery: Ancient Sex Toy? to list only a few).  It certainly looks like a penis.

The object is carved antler measuring 10.5 cm (4 in) long by 2 cm (0.8 in) in diameter (the ruler above is in cm).  The artifacts are estimated to come from 4,000 - 6,000 BCE and I'm guessing the antler material will be radiocarbon dated to get a better fix on its age.  It's not the oldest phallic object discovered, in 2005 archaeologists unearthed a siltstone phallic object in Germany dating back some 28,000 years.  This object was also called a dildo in press releases.

Were these objects, in fact, sex toys?  I'm puzzled by the fact that the Motala antler phallus-shaped object looks like a circumsized penis. We wouldn't expect that in stone-age northern Europeans.  Let's look at it again and get a better perspective on its actual size.

This is not the picture they put in most of the news stories (they used the one next to the ruler that most readers, at least in this country, would think was in inches making it appear dildo-sized).  The object in the picture above doesn't look like a sex toy even though it obviously has a phallic shape.

We'll probably never know what these were used for but there may be more prosaic explanations.  Would people have been as eager to read news stories titled "Archaeologists unearth flint knapper tools"?  The German object bears scars of having been used to knap flint and was reassembled from 14 fragments.  The Motala antler phallus may have been used in flint knapping as well - a conclusion strengthened by seeing the entire object (with its broken tip).

Now it looks a little more like a tool, doesn't it?  One with a rounded knob to fit into your palm while you used the point to push flakes off flint arrowheads?

Some have speculated that it was simply a tent stake.  The people of the time probably lived in wood-frame wickiup-type structures draped with caribou (reindeer) skins.

Then again, maybe it had some ceremonial significance.  It could be the male ritual equivalent of the widespread Venus figurines found throughout Europe.

That's the challenge of archaeology.  Find objects and try to figure out what the hell they were.  Coming up with titillating explanations gets press and, perhaps, more research money (a precious resource in science).  While this find is interesting, I think it was definitely hyped up by the researchers.

Thursday, August 12, 2010

Magical Mecca

The Saudi Arabians are building a giant clock tower in Mecca which is meant to outdo St. Stephen's Tower (which houses Big Ben) in London.  The tower in London is 316 feet high with a 23 foot diameter clock face.  The Saudi tower will be 2,000 feet high (the 2nd tallest building in the world) and the clock face will be 151 feet in diameter.  Muslims will be reminded to pray 5 times a day when 21,000 lights flash bright enough to be visible 18 miles away.

I guess we're all helping pay for this every time we fill up our gas tanks but it's their money.  If they want to build gigantic clocks with the billions we contribute to their economy, it's their business.

This article out of England in the Telegraph tells all about it, and then gets seriously weird (why I'm posting about this otherwise uninteresting news).  It seems some Muslims are annoyed about the fact that the standard of time around the globe is based on the time at longitude 0° - the site of the Greenwich Royal Observatory in southwest London.

The location of a zero line of latitude, the Equator, is easy to understand - it divides the Earth into a Northern and Southern Hemisphere based on its axis of rotation.  Longitude lines, however, can start anywhere.  A line running through the Royal Observatory was chosen as the Prime Meridian by English cartographers back in the 1700s because England needed accurate maps for seafaring and Britannia ruled the waves.  An international conference in 1884 made it official, the Prime Meridian ran through Greenwich.

In science, navigation, communication, etc., the time at the Prime Meridian (synchronized by atomic clocks around the world) is standardized as Coordinated Universal Time (abbreviated UTC).  It's five hours ahead of Eastern Standard Time here in NY (4 hours ahead now since we're in daylight savings time and UTC doesn't change even though we "sprang ahead" on March 14).

World time zones 

Apparently, some in the Arab world don't like the fact that the time on clocks in London (Greenwich Mean Time) is the same as UTC.  They see it at as Eurocentrism and their agenda, according to a Muslim quoted in the article, is "Putting Mecca time in the face of Greenwich Mean Time. This is the goal."

There are good reasons for putting the Prime Meridian in England.  It means that the International Date Line, one the opposite side of the Earth, is in the middle of the Pacific Ocean where it doesn't inconvenience too many people.  If the Prime Meridian were in Mecca, the date line would run through the middle of Alaska.  Inconvenient for people living there.  We could switch but, at this point, why bother - it would just work up all kinds of nationalistic furor around the world (before the Prime Meridian was set at Greenwhich, various countries wanted to locate it at Copenhagen, Rome, Jerusalem, St. Petersburgh, and even Philadelphia).

Now the article gets strange:

According to Yusuf al-Qaradawi, an Egyptian cleric known around the Muslim world for his popular television show "Sharia and Life", Mecca has a greater claim to being the prime meridian because it is "in perfect alignment with the magnetic north."

I have no idea what the hell that means.  If I face toward magnetic north, I'm in perfect alignment with it too.  Here's some more:

This claim that the holy city is a "zero magnetism zone" has won support from some Arab scientists like Abdel-Baset al-Sayyed of the Egyptian National Research Centre who says that there is no magnetic force in Mecca.  "That's why if someone travels to Mecca or lives there, he lives longer, is healthier and is less affected by the earth's gravity," he said. "You get charged with energy."

Pure pseudoscientific nonsense.  Makes me wonder about the Egyptian National Research Centre.  If Mecca were a "zero magnetism zone" then compasses wouldn't work there, a trivial claim to test (and falsify).  The "charged with energy" business is just woo.

What they may be talking about, however, is the zero line of magnetic declination.  Turns out the north magnetic pole is not in the same place as the north geographic pole (which is fixed and located at the Earth's rotational axis).  The north magnetic pole is in the Canadian Arctic around 83° N latitude, 114° W longitude.  The Earth's magnetic field is generated in the iron core of the Earth and wanders with time (currently around 60 km/year).

Look at the diagram above which shows lines of magnetic declination for the Earth's magnetic field.  It's very complex, monitored and studied by geophysicists, and changes slightly year-to-year.  Note the zero line that passes through the middle of the U.S.  This means that if I go to the middle of Minnesota, for example, my compass (which aligns to magnetic north) will point to true north (0° declination from north).  Here in the Hudson Valley of New York, however, my compass will still point to magnetic north, but it will now be about 13.24° west of true north (13.24° W declination).  Out in Seattle, my compass might be almost 17° E of true north!  If you're doing geologic mapping with a compass, you have to account for magnetic declination or things won't be accurate to true north.

Is Mecca on a 0° declination line?  Not exactly.  It's close, as you can see on the diagram above, but not right on it (like some sites in the North and South America are).  NOAA's National Geophysical Data Center calculates a magnetic declination of 3° E for Mecca.  Anyway, if being on a zero line of magnetic declination makes one "lives longer, is healthier and is less affected by the earth's gravity" then we should all move to the middle of Minnesota (I've been there - I'll pass).

Funniest comment I read about this article (but an obscure reference for most people) is that the Muslim fundamentalists making these claims are the Juggalos of Arabia (watch this NWS video which made the rounds on numerous science blogs a few months ago to understand).

Wednesday, August 11, 2010

Lunar phases and the goddess

In observational astronomy classes, one of the first things students learn about are how the phases of the Moon work.

Notice how a new moon exists when the Moon is between the Sun and the Earth such that its far side (the side we never see from Earth) is lit while the side facing us is dark.  It's also overhead during the day so we simply don't see it. 

Next we have a waxing crescent, first quarter moon, waxing gibbous, and full moon.  Note that the right side of the Moon, as seen from the Earth, is getting progressively more and more lit as you advance towards the full moon.

The full moon occurs when the Moon is on the opposite side of the Earth from the Sun so the side facing us is now fully lit.  The Moon's also high overhead in the middle of the night making it easy to spot in the sky.

From the full moon, we then see a waning gibbous, third quarter moon, waning crescent, and finally the new moon returns.  During the waxing phase of the lunar cycle, the left side of the moon is lit less and less with each passing day.

This cycle, from new moon to new moon, takes 29.53 days (29 days, 12 hours, and 44 minutes).  Note that the phases are simply due to the geometric orientation of the Moon, Earth, and Sun and the simple fact that the half of the Moon facing the Sun is lit and the half facing away from the Sun is dark (just like the Earth).  As the Moon orbits the Earth, we see the lit and unlit portions at different angles.  Contrary to popular belief, the phases of the Moon have nothing to do with the shadow of the Earth on the Moon (lunar eclipses do, but that's a different story).

One thing that students often have a hard time remembering is which half of the Moon is lit when it's waxing (right side) and which side is lit when it's waning (left side).  One easy way to do so, at least for me, is to remember the symbol shown below.

This is a Wiccan symbol representing the goddess (who is associated with the Moon).  The left side represents the waxing crescent moon (right side of the Moon lit), the middle circle represents the full moon, and the right side represents the waning crescent moon (left side of the Moon lit).  The symbol is sometimes called the Triple Goddess since it represents her three aspects as maiden, mother, and crone (waxing, full, and waning).

While scholars debate about the origin of this symbol and the religious beliefs of ancient European cultures, we can say with certainty that ancient cultures around the world had an intimate familiarity with the cycle of lunar phases - it was, after all, how you kept track of time before calendars were invented.  Remember this symbol and you'll instantly know, when looking at a crescent, quarter, or gibbous moon, whether it's waxing or waning in its neverending cycle of phases.

Tuesday, August 10, 2010

Chestnut Oak

One very common tree on the Shawangunk Ridge where I frequently hike is the chestnut oak (Quercus prinus).  So named because the leaves resemble the chestnut tree more than a traditional oak tree leaf.  Chestnut (Castanea dentata) leaves, however, are more saw-toothed and you obviously won't see acorns on a chestnut tree.  It's also sometimes called a rock oak due to its appearance on rocky ridge tops in the Northeast (which is why it's common in the Shawangunks).

Full-grown, the acorns are some of the largest of all the oaks.  When they drop, they provide food for lots of woodland wildlife including squirrels, chipmunks, mice, turkeys, and even deer.  Just from casual observation in the woods this summer, the acorn crop seems pretty heavy this year.

Chestnut oaks are one of the easier trees to learn how to identify.

Monday, August 9, 2010

Pet peeve of the day - Rulers

It never occurred to me that there are adults who are incapable of correctly using a ruler.  That is until I started teaching college-level geology labs.

Typical rule with metric and English measurements.  Following are two things commonly seen with college students when using a ruler to measure features on topographic maps. 

First common error is that they'll measure something that's 3 cm in length but they'll report that it's 3 mm in length.  Why?  The ruler has mm printed on the metric scale so they think each number is a mm.  By the way, I've had students tell me, in all seriousness, that they were never exposed to the metric system in public school.  I have no idea if that's true or the student was just sleeping on those days but they swear it's all new and magical to them.

Second common error is that they'll measure something as 3 in plus, let's say, 3 tick marks and report it as 3.3 in.  They don't realize that English units on virtually all rulers are divided into eighths (or sixteenths), not tenths, and they're not the same thing (3 3/8 = 3.375).  Good thing they're going to college and not trying to be something useful like carpenters ("I just can't understand why these floor joists are all too short!").

Don't kids learn to read rulers in, like, third grade?  Don't even get me started on protractors - half the class can't use those high-tech instruments (they measure the angle from the bottom of the protractor, not the 0° line, or measure from the right-side and call an acute 50° angle an obtuse 130°).

I'm not big on tattoos but here's one that might actually be useful...

Of course if we ever switch to metric he'll be S.O.L.

Sunday, August 8, 2010

Perseid meteor shower

After midnight in the early morning hours of either Thursday, August 12 or Friday, August 13 will be the best time to view the annual Perseid meteor shower.  It's just after the new moon on the 9th so the skies will be nice and dark (assuming it's clear - not always a sure bet in the frequently-cloudy Hudson Valley).  These dates are only when the shower peaks, by the way, any meteors seen between July 24 - August 24 are generally Perseids as well.

The Perseids are named since they radiate from the portion of the sky where the constellation Perseus is located.  Perseus rises in the northeast around 11 pm and gets progressively higher in the sky after midnight in the early morning hours.

The Perseids exist because the comet Swift-Tuttle has left a trail of debris around that part of the Earth's orbit which are swept down into the Earth's atmosphere leaving a glowing trail of their own self-destruction.  Virtually all of these particles are dust-sized grains and disintegrate without leaving a meteorite to strike the Earth's surface.

Swift-Tuttle was discovered in 1862 and returned in 1992.  Next time will be in 2126 after we're all dead and gone.  The interesting thing about Swift-Tuttle is that it's big (27 km across) and crosses Earth's orbital plane.  If it ever struck, we'd all become extinct (the asteroid that knocked out the dinosaurs was only 10 km across).  Not to worry, while the 2126 pass will be close, leading to Swift-Tuttle being a bright, spectacular comet, it's not close enough to hit us (and we'll all be dead and gone, anyway, remember?).

So why are meteor showers best after midnight?  Look at the diagram below:

Which position, A or B, will show the debris entering the Earth's atmosphere best?  Position A is just after sunset on the trailing side of the Earth while position B is before sunrise (after midnight) on the leading side of the Earth in its orbit around the Sun.  At position B, we're plowing right into the debris field left by comet Swift-Tuttle and the meteor shower will be at its best.  Continuing on in that direction is the constellation of Perseus - the radiant of the meteor shower.

Even better, earlier in the evening, there will be a nice conjunction of planets visible in the western sky from about 9 pm or so, when it gets dark, until around 10 pm when they set.  Venus, Mars, and Saturn will be easy to find as they're clustered around bright Venus just above the crescent waxing moon.

As an added bonus, a nice, bright Jupiter will be visible in the eastern sky after midnight (it will be the brightest "star" in the sky over there).  Perseus will be left of Jupiter if you're facing east and below the W of Cassiopeia.

So, if it's clear next Wednesday or Thursday, pull an all-nighter (those get increasingly difficult with advancing age, don't they?) and lay out in your lawn chair and enjoy the celestial show.

Saturday, August 7, 2010

Pileated woodpecker

I was told, by a naturalist on a hike at Lake Minnewaska earlier this summer, that big rectangular holes like this one in a dead hemlock (Tsuga canadensis) are made by pileated woodpeckers (Dryocopus pileatus) looking for insects.

Pileated woodpeckers are crow-sized and the largest woodpecker in North America.  They're year-round inhabitants of forests here in the Hudson Valley but relatively shy and hard to spot.  Once seen, however, they're easy to recognize due to the distinctive red crest on the back of their heads (both males and females).  The generic name Dryocopus means "oak-tree cutter" and pileatus refers to a "skullcap" and obviously due to the bird's bright red crest.

Image from Wikipedia

Pileated woodpeckers have a distinctive call (listen here).  I do hear them occassionally in the woods behind my house and have also heard them on hikes on the Shawangunk Ridge.  I also hear drumming sometimes but I'm not sure if it's a pileated or one of the other local woodpeckers (in the winter, hairy (Picoides villosus) and red-bellied (Melanerpes carolinus) woodpeckers are frequently seen at our suet feeder.  I've only seen a pileated woodpecker once, briefly, on a tree across the road from my house a few summers ago.

Next time you're out hiking, take a little time to sit quietly in the woods and listed for a bit.  You might hear the wild laughter of this amazing bird.