Seismogram of Chilean Earthquake

Below is a seimogram showing the Chilean earthquake which occurred around 0634 UTC.

The seismogram is from the Lamont-Doherty Earth Observatory in Palisades, NY!  That's why it shows the earthquake occurring at 6:46 GMT (same as UTC).  The quake occurred at 6:34 but the seismic waves had to travel through the interior of the Earth from Chile to New York - it took about 12 minutes!

Chilean Earthquake

A massive 8.8 magnitude earthquake hit Chile at 0634 UTC (1:34 am EST) today (Saturday, February 27).  Click on the link for information from the National Earthquake Information Center (NEIC).  The epicenter was offshore about 200 miles SW of Santiago.  The depth was 35 km (a bit over 20 miles).  Since the initial earthquake, as of 7:00 pm EST as I write this, there have been 7 aftershocks greater than magnitude 6 and dozens greater than magnitude 5.

Coastal Chile is no stranger to earthquakes.  The largest historic earthquake in the world was the Chilean Valdivia Earthquake of May 22, 1960 with a magnitude 9.5 on the moment magnitude scale (most people don't realize that seismologists don't use the Richter scale anymore - I'll write about this at some point).  The 1960 earthquake spawned a tsunami that killed some 200 people in Hawaii, Japan, and the Philippines - a concern today and the Tsunami Warning Center issued a warning for the Pacific basin.

Why are there big earthquakes in Chile?  Plate tectonics.  A large slab of the Pacific Ocean floor off western South America called the Nazca Plate is sliding (subducting) underneath South America.  The boundary between the Nazca and South American plates is a deep seafloor trench called the Peru-Chile Trench and the plates are converging at a rate of about 8 cm/yr.  As the plate slides down into the trench (and ultimately into the Earth's mantle beneath), it sticks.  Stress builds up over the years and eventually something snaps and the plate slips a few meters.  Seismic waves of energy radiate outward in an earthquake.  The 1960 earthquake, for example, released 250-350 years worth of plate movement in a few seconds.

Today's earthquake occured right between the 1960 earthquake to the south and an earlier 8.5 earthquake in November, 1922 to the north.  It's a portion of the subducting plate that hasn't slipped in a while. While no one can yet predict when an earthquake will occur in a specific area, geologists certainly aren't surprised by this one.

We're all going to die!

No, not from a nor'easter snowstorm (watch the news and you'd think it's never snowed in the northeast in February before).  We've got a woodstove, candles, and plenty of food and books if we lose power (and even camping equipment to cook with and lanterns if power's out for a while).  At most, I'll suffer anxiety for being unable to check my email and read blogs (yes, I'm an Internet addict)!

The title of this post rather refers to a book I'm currently finishing up called Death from the Skies! These are the Ways the World Will End... by Dr. Philip Plait of Bad Astronomy fame.

Plait provides and entertaining look at all of the ways the universe could kill us - all of us.  He includes discussions of asteroid impacts, massive geomagnetic storms, supernova, gamma ray bursters, black holes, and even alien attacks!

The best thing about his book, unlike those awful specials on cable TV, is that it's firmly rooted in science.  Many of the possible ways the universe could kill us, Plait explains, are so statistically unlikely as to be virtually impossible (e.g. a nearby supernova) while others are a virtual certainly - at least on a long-enough time scale (e.g. asteroid impact).

Reading this book will teach you a lot about basic astronomy.  Stellar evolution, for example, is covered in a lot of detail when discussing the eventual fate of our Sun, supernova, and the formation of exotic objects like neutron stars and black holes.

I've been reading the book at night before I fall asleep.  I'm surprised I haven't had any nightmares yet - there's a lot to worry about!

Yet more snow

It's been snowing all day here in the Hudson Valley with a forecast for snow tomorrow as well.

Here's a neat website on snowflakes which seems appropriate.  There are a lot of beautiful images to enjoy.

Where have all the bats gone?

If you're in the New Paltz area, there's an interesting free lecture Thursday night, February 25 on the SUNY New Paltz campus (Lecture Center 100) at 7:00 pm.  "Bats on the Wane" by Carl Herzog, a wildlife biologist with the NYSDEC. 

If you don't know, bats have been dying off in record numbers locally (and throughout the northeast) from a fungal disease known as White Nose Syndrome (WNS).  Bat hibernacula in the local Rosendale cement mines have been especially hard hit.

I plan to attend (weather permitting).  More information is available on the Mohonk Preserve website.

Interpreting Genesis

Evolutionblog has a great post about Interpreting Genesis.  The author, Jason Rosenhouse is responding to an essay by Kenton Sparks, a professor of Biblical Studies at Eastern University.  Basically, Sparks argues that the Bible was never intended as a science book and that's where modern creationists err in believing it to be one.

Rosenhouse disagrees and writes [about creationists]:

"Nor do they believe that the early chapters of Genesis were intended primarily to teach us science. In their view the function of these chapters, as with the rest of the Bible, was to give us information relevant to understanding our predicament as sinful human beings.

However, they do believe the Bible is inerrant on any subject it addresses, and if that means accepting what it says during its very rare excursions into science then so be it."

Bingo.  Some people believe on can argue with young-earth creationists by discrediting their bad ideas about science.  Nope.  Some people think we can get around the conflict between science and scriptural literalists by claiming that "Genesis is not a science book" (Kenton Sparks' argument).  No again.

To really understand where young-earth creationists are coming from, you have to realize that their entire theology is bound up in a literal interpretation of Genesis because that explains why there's evil in the world, why man needed salvation, etc.  That also entails, by necessity, a belief in a young-earth and divine creation, not just of man, but of all life since there was no death before the fall in the Garden of Eden.

Giving up a belief in a 6,000 year-old world is tantamount to giving up a belief in God.  Science isn't going to easily win that argument.

Interesting Math Column - IV

Yet another math column in the NY Times by Cornell mathematician Steven Strogatz.  This week it's titlted Division and it's Discontents.  He makes the point that the natural numbers (1,2,3...) are good enough if all we want to do is count (addition and multiplication).  He covered this in the From Fish to Infinity and Rock Groups columns.  Once we start subtracting, however, we need to add negative numbers to our counting numbers to form the integers (...-2,-1,0,1,2...).  The was dealt with in The Enemy of My Enemy column.

Division, now dealt with in this column, creates an entire new set of numbers - the rational numbers (they can be expressed as a ratio like 1/2 or 22/7).  Turns out that this infinite set of rational numbers is actually the exception - most numbers are actually irrational - different levels of infinity (I'm sure Strogatz will discuss the concept of infinity in a later column).

This is probably where many people's understanding of math starts to fall apart.  Concepts start to become less concrete and outside of our day-to-day experience.

Blacks in Geosciences

February is  Black History Month so I thought I'd post something relating to this topic and geology.

I was recently made aware of a paper titled Untapped Talent: The African American Presence in Physics and the Geosciences.  While the paper was published in 2008, and uses data which runs only up to 2004, I'm sure the numbers are still very similar today.

The bottom-line message of the paper is that even though there are many blacks who do well in mathematics in high school, they generally do not go on to study either physics or the geosciences.

The paper had some interesting (and incredibly low) statistics about blacks in the geosciences:

  Bachelor's degrees in geoscience earned by blacks (2004) = 2%
  Master's degrees in geoscience earned by blacks (2004) = 1.2%
  PhD's in geoscience earned by blacks (2004) = 1%

Numbers have been improving although totals are still very low.  For example, between 1975-1980, 0 black women and only 8 black males earned PhDs!  Between 1999-2004, it had increased slightly to 13 females and 29 males.  This is nationally!  Compare this to the total of 686 PhDs in geosciences for 2004.

Obviously, if there are so few PhDs granted to blacks in geosciences, there are not going to be a lot of black geoscience professors as role models either.  These numbers have certainly mirrored my experience in higher education as both a student and professor.

I went to the Census Department's website and obtained the following information:

  Blacks in USA (2008) = 12.8%
  Blacks in New York State (2008) = 17.3%
  Blacks in Ulster County (2008) = 6.5%

Despite this, at the two-year community college where I teach, I have never had, in over 10 years, a black student majoring in Math/Science with an Earth Science concentration.

Why?  I don't know.  What can we do to change this?  I have no idea.  I would like to encourage more minorities to enter the geosciences (everything said here could apply to hispanics as well) but, quite honestly, I have no idea how to do so.  Many of our geology students enter the major after taking an introductory Earth Science 101 course to satisfy their science elective (every student needs to take a science course) and thinking "Hey, I like this!"  I've also had minority students in these 101 courses but, for whatever reason, they have never expressed an interest in learning more about the field.  And it's not just my courses as the national numbers show.

If anyone has any ideas, let me know.

Here's a link which may be of interest: National Association of Black Geologists and Geophysicists.

Picture of the Week - Stark's Knob

The picture below is of Stark's Knob - a rocky hill just north of Schuylerville, NY.  It's near the banks of the Hudson River and about 10 miles east of Saratoga Springs.  This hill tells two stories which are separated by around 450 million years of time.

Let's start with the more recent story first.  It happened only 233 years ago...

As summer moved into fall in 1777, the Revolutionary War wasn't going well for the colonists.  The British General John Burgoyne from Quebec was planning to move down through Lake Champlain and then into the Hudson Valley.  British troops were also supposed to be led from the Great Lakes down the Mohawk Valley toward Albany.  Finally, General Howe was to have come up the Hudson Valley from New York City.  These three advancing columns were to meet up and effectively divide the colonies in two - the war would soon be over and the British victorious.

It didn't work out as planned.  The column from the west got held up at Fort Stanwyx near the present-day city of Rome, NY, where they met fierce resistance.  Through an apparent miscommunication, General Howe sent his army to Philidelphia that fall, rather than up the Hudson.  It was left to General Burgoyne.

It all culminated at the Battle of Saratoga - really a series of skirmishes in September and October.  General Horatio Gates and Major General Benedict Arnold commanded the American forces.  If Arnold had died at Saratoga, he would be remembered today as a great American hero for his actions there.

The Battles of Saratoga did not go well for the British and by October 10 they were under seige by the Americans.  As Burgoyne attempted to retreat to the north, General John Stark "corked the bottle" by positioning his troops between the Hudson River and the hill now known as Stark's Knob on the 12th trapping the British and leading to their surrender a few days later.  This major defeat of the British is seen by many as the turning point of the war.

 The Surrender of General Burgoyne by John Trumbull (1822)

It's a great story and when standing on top of Stark's Knob, one can visualize in your mind's eye those long-ago movements of troops across the landscape.  To a geologist, however, Stark's Knob has another history, this one stretching back some 450 million years into the past.  Below is a close-up of the rocks forming the knob.

What is this?  Turns out it's basalt - hardned lava.  Not just any basalt, either.  It's pillow basalt (note the rounded shape).  Pillow basalts form when lava is erupted under the oceans - the cold water instantly cools a rind around the erupting lava and it oozes out like toothpaste being squeezed out of a tube forming rounded masses on the seafloor.

Why was this seafloor and why was lava erupting here?  Turns out that 450 million years ago, this part of proto-North America was south of the equator and under water.  It started out as a shallow continental shelf but became downwarped into a deeper basin as the seafloor was subducted down an approaching trench.  The trench was the plate boundary between us and a chain of volcanic islands relentlessly approaching closer each year.

Image from the United States Geological Survey (USGS)

As the island arc approached, the seafloor flexed downward, fractured, and erupted lavas.  Eventually the volcanic arc collided resulting in a mountain building event called the Taconic Orogeny - Rocky Mountain sized peaks right here in eastern New York State!  That collision thrust up a slice of the ancient seafloor and emplaced it here near the banks of the present-day Hudson.

Both stories are interesting and I share both when periodically bringing students to this neat site.  It's great to get students to think about connections between various disciplines like history and geology (which is really just history extended far, far back beyond humans).

Legislating "science"

Idiot politicians in the South Dakota legislature recently passed, by 36-30, Resolution 1009 which calls for "balanced teaching of global warming in the public schools of South Dakota."  Similar to the bills occassionally popping up in Bible-belt states calling for "balanced" teaching of evolution (in other words, attempting to insert creationism pseudoscience in public schools), this bill is full of completely erroneous statements of fact and a naive misunderstanding of the words "theory" and "fact" in science.

Read what the resolution says and then go to a reputable site like RealClimate (run by climate scientists) and learn how much of it is complete nonsense. I'm always amazed at the hubris shown by politicians and political commentators (most of whom, I'd be willing to bet, have never had a college-level lab science course) who think that they're experts on a subject area whose practioners have had years of graduate work in science and decades of research experience.  Efforts by politicians to interfere with science education should always be vigorously opposed (anyone today remember Trofim Lysenko?).

I do, however, agree with one statement in the resolution - "the debate on global warming has subsumed political and philosophical viewpoints which have complicated and prejudiced the scientific investigation of global warming phenomena."  The complications and prejudice, however, come from politicians who know nothing about climatology, atmospheric chemistry, or the practice of science.

Governor Closing New York's Parks

Our governor (I don't dare tell you what I really think of this guy) has decided to close a number of state parks for budgetary reasons.

This includes Thacher State Park west of Albany - a place I bring students to every year for my geology classes.  Thacher is a beautiful place as well as a premier geologic locality with incredible exposures of Devonian Helderberg Group limestones and fossils.  Here's an online petition if you'd like to express your displeasure.

Students hiking Indian Ladder Trail at Thacher.

Interesting Math Column - III

The past two weeks, I had posted about an interesting math column (From Fish to Infinity and Rock Groups) by Steven Strogatz, a Cornell math professor, who is writing a series of articles for the New York Times about mathematics.

The third installment is now available here and is titled The Enemy of My Enemy.  Not as interesting to me since I'm more interested in the pure mathematical side of things than in balance theory and geopolitical alliances.

Dietrich Werner (1942-2009)

This is a bit late, Dietrich passed away suddenly on December 15 and his memorial service was on January 23.  I did, however, want to say something about him and acknowledge the kindness he showed to me and my students.  Here's a picture of Dietrich in his beloved Widow Jane mine in Rosendale talking to my students about the 19th century Rosendale Cement industry.

Dietrich was only an acquaintance. Someone I'd chat with for a bit if I ran into him at a town meeting or a conference.  Someone I'd call a couple of times a year to ask if I could bring a van load of geology students down to the Widow Jane mine (he always welcomed us).  He was a kind, incredibly knowledgeable, and generous man.

What affected me the most about Dietrich's death was that the week he died I was working on a project having to do with the Rosendale Cement industry and I was thinking of calling him the following week to get together to discuss it.  He knew more about this topic than anyone I know.  Researching local history was a labor of love for him and a lot of local knowledge passed away when he did.

We always assume we have all the time in the world.  We don't.  Life is short.

An obituary is posted here if you'd like to read more about his interesting life.

Picture of the Week - Magnetite Mine

Below is a picture taken of a magnetite iron mine in Harriman State Park I visit with students in my summer Geology of the Hudson Valley field course.

Magnetite (Fe2O3) is an important ore of iron.  As its name implies, it's also magnetic.  This mine is in Harriman State Park - a region known as the Hudson Highlands.  The geology of the Hudson Highlands is very similar (identical, really) to the geology of the Adirondacks and both regions actually represent the highly metamorphosed and deformed rocks which underlie all of New York State (much of the East Coast, actually). 

This area of crust is known as the Grenville Province and represents rocks formed during an ancient collision between two blocks of continental crust (proto-North America and Amazonia) between 1.3-1.1 billion years ago.  That collision, much like the more modern collision of India with Asia, built a Himalayan-scale mountain belt running through what's now New York State.  Deep in that mountain belt, rocks folded and metamorphosed due to the extremely high temperatures and pressures present some 12 miles below the peaks of those mountains.  Those are the rocks we now walk on at the surface in the Adirondacks or Hudson Highlands (elsewhere in the state, these ancient basement rocks are covered by thousands of feet of younger sedimentary rocks).

A bit over 900 million years ago, hot fluids circulated through fractures and faults in these deeply-buried rocks.  These iron-rich fluids precipitated crystals of magnetite within these linear fracture zones.  In other places, like the Sierra Nevada Mountains in California, similar fluids at other times precipitated minerals like gold but we got iron.  Iron, however, is a valuable mineral resource.

In the 1700s, settlers discovered and started mining iron ore in the Highlands.  It's actually relatively easy to find - you can walk along with a compass and when the needle deflects, you're walking over a vein of magnetite iron ore.  Magnetite is also easy to recognize being black and very dense.  The abundant trees and water power in the Highlands led to the development of furnaces to smelt and utilize the iron.  It became very important to the colonists during the Revolutionary War and was used to forge cannons, tools, and the famous chains across the Hudson.

With the discovery of iron ore in the Mesabi Range of Minnesota and the Upper Pennisula of Michigan (with cheap shipping on the Great Lakes), iron mines in the Highlands (and up in the Adirondacks) gradually were abandoned.  Today, all that's left are these gashes in the woods, often flooded with groundwater, and small piles of overgrown waste material next to the mines.

Everything You Know About Indians Is Wrong

I just finished a new book titlted Everything You Know About Indians Is Wrong by Paul Chaat Smith. Smith is a curator for the National Museum of the American Indian in Washington, D.C. (a great place, by the way, I've been there twice) and of Comanche descent.

It's an uneven collection of essays (some are a bit too artsy for my taste) on what it's like to be a Native American in modern America. Lots of interesting cultural observations based on his experiences which range from growing up in a suburb with middle-class parents to his involvement in the American Indian Movement (AIM) to being a museum art curator today.

One thing that resonated with me is the following observation from one of the last essays in the book:

The country can't make up its mind. One decade we're invisible, another we're dangerous. Obsolete and quaint, a rather boring people suitable for schoolkids and family vacations, then suddenly we're cool and mysterious. Once considered so primitive that our status as fully human was a subject of scientific debate, some now regard us as keepers of planetary secrets and the only salvation for a world bent on destroying itself.

Heck, we're just plain folks, but no one wants to hear that.

I have to admit to being guilty of some of those romanticizations myself. I've been to reservations like Pine Ridge in South Dakota and the Navaho and Hopi in Arizona to see the Indians like they're some sort of tourist attraction (although, to be fair, I also went to those places to see things like the SD Badlands and Canyon de Chelly in AZ).

It's hard for me personally to view them as just plain folks when I attended a powwow in the middle of Pine Ridge put on, not for tourists, but for the people of the community. People I'm related to here in the mid-Hudson Valley of NY don't do those kinds of things (we just BBQ and overeat when we get together).  Although, I suppose I would have the same difficulty relating to Ukrainian communities, for example, that dress up and do traditional dances similar to what I saw the Lakota do in Pine Ridge.

More seriously, Smith himself undercuts his claims to being just plain folk by frequently mentioning the fact that Indians in America have a unique cultural perspective that people like me (i.e. white) lack.

As an aside, noting the book's title, one interesting thing that I've noticed is that the only people who use the phrase "Native Americans" are educated white people. On every reservation I've been through, the people living there either refer to themselves collectively by their tribal name (Lakota, Diné, Makah, Akwesasne, etc.) or simply as Indians, however politically incorrect and geographically inaccurate that term is viewed by modern scholars. I just can't bring myself to call them Indians (I guess it's because I'm an educated white person myself).

Anyway, it's an interesting book and worth reading.

4th Amendment, we don' need no stinkin' 4th amendment!

The Fourth Amendment to the Constitution reads:

"The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."

That pesky Bill of Rights.  There's a reason police can't just storm into your home and tear it apart looking for evidence against you unless they obtain a warrant from a judge for "probably cause."  In 1967, in the case of Katz vs. United States, the Supreme Court ruled that this amendment gave us "a reasonable expectation of privacy."

So far so good.  Enter President Obama's Department of Justice which will argue before the U.S Court of Appeals that our goverment does not need a court-ordered warrant to obtain cell site location information from mobile phone carriers.  In other words, the government will be able to track you, via your cell phone, for whatever reason they like, even if you're not engaging in criminal activity.  Obama's Department of Justice has argued that warrantless tracking is permitted because Americans enjoy no "reasonable expectation of privacy" in their cell phones' (and your) location.

Interesting case.  I'm sure you can guess where I stand on this given the way I've written this post (yes, I support the Constitution of the United States and the Bill of Rights - call me a radical!).

Anyway, I think if the Bush Administration had proposed this, the hue and cry would be much louder than what little criticism I've seen of this case to date.  What exactly has Obama changed?  Reminds me of The Who's Won't Be Fooled Again - "Meet the new boss, same as the old boss."

What's the phase of the Moon?

Ever want to know what the phase of the moon was, is, or will be on some day?  This is a neat Moonphase Calculator that works for any month from 1900-2100 CE.

Snow, snow, snow

News article on how there's snow in 49 out of the 50 states - Hawaii being the only exception.

While a common remark to such news is often a sarcastic "damn global warming!" (I've jokingly said it myself), it's important to realize there's an important difference between weather and climate.  Weather is the day-to-day stuff and sometimes it's hotter than normal and sometimes it's colder than normal.  What's "normal"? 

I can go to a National Weather Service (NWS) website and get weather data for Poughkeepsie, NY (the closest NWS station to where I live).  Today's high temperature was 31 F.  The normal high temperature for this date was 37 F so it was colder than normal today (Saturday, February 13).  Where did this "normal" value come from.  It came from taking the high temperatures for February 13 from 1971 to 2000, adding them together, and dividing by 30 years.  That's how climate is defined - a 30 year average.  We currently use 1971-2000 but on February 13, 2011, the "normal" temperature will be defined as the 30-year average from 1981-2010 (it will switch over on January 1, 2011).

In other words, a bitter cold winter someplace with lots more than normal snowfall doesn't mean global warming isn't true.  One storm or even one winter does not equate with longer term climate change.  If I look at the NWS monthly data report for January 2010, we see that the average monthly temperature was 26.1 F which was 1.6 F warmer than normal. So far February is running a bit colder than normal but the month is only half over.

Wild worm sex

The perfect Valentine's Day gift for all you biology geeks out there.  The copulating earthworm necklace in sterling silver.  I think you'd need an unusual wife to get away with this present.  (Found this information on the Biophemera blog).

Picture of the Week - Horn Coral

Along Route 209 near Kingston, between Route 28 and Sawkill Road are a series of outcrops along both sides of the road.  Cliffs and hills of shale interbedded with thin layers of sandstone.  These rocks belong to what's known as the Mount Marion Formation (after a town up the road a bit) which is part of what's called the Hamilton Group (a regionally extensive series of rock formations). 

If you know where to look along these outcrops, being careful not to get run over by all the speeding cars on Route 209, it's relatively easy to find weathered out coral fossils like the one below.

This is actually a fairly large specimen, most are a bit smaller (some of the smaller ones actually preserve better details as well).  This belongs to a group of corals (phylum cnidaria, class anthozoa) that are called the rugose corals (many people call them horn corals because of their shape).  Rugose refers to their wrinkled appearance (this one's been weathered smooth). 

This particular species lived during the Devonian Period of geologic time (359-416 million years ago).  A little searching can also turn up shelled fossils called brachiopods and even a marine snail (gastropod) or two. Below is a reconstruction of a Devonian seafloor with some rugose corals (among other things).

This is basically what Kingston looked like during the Devonian Period.  A shallow, warm, subtropical sea floor.   The evidence is right there laying in shale chips in ditches along the side of the highway!

As time goes by...

I was looking through some pictures today on my computer and found the following...

Me and my daughter a few years ago walking near Spring Farm at the Mohonk Preserve on the Shawangunk Ridge (Rondout Valley and Catskills in the background).  She turned 9 last week.  She'll be a teenager soon.  Here's another...

Time passes too quickly.

Interesting math column - II

Last week, I had a post about an interesting column (From Fish to Infinity) by Steven Strogatz, a Cornell math professor, who is writing a series of articles for the New York Times about mathematics. 

The second installment is now available here and is titled Rock Groups.  Nothing new for me, I've always enjoyed playing around with number theory (at least at a very elementary level!).

I do look forward, however, to reading The Housekeeper and the Professor and A Mathematician's Lament - both referenced in the article.

Why Mars is bright

A few days ago (January 29), I posted about how Mars was nice and bright and located near the full Moon.  Mars has been about as bright as the star Sirius which is the brightest true star in the sky (planets sometimes get a little brighter).  A student asked me today why Mars was so bright lately.  The following figure should illustrate the reason:

Looking down on the inner solar system, we see that Mars and Earth are lined up on the same side of the Sun.  Astronomers would say that Mars is at opposition (opposite from the Sun).  It's relatively close to us and catching lots of sunlight to reflect back so we can see it so brightly as a reddish "star" in the night sky.

It's currently in the constellation of Cancer, halfway between Regulus in Leo and Castor and Pollux in Gemini (about half-way up in the eastern sky around 8 pm in our area).  Go out and take a peek, it's unmistakable.

Picture of the Week - Horrible cruelty

A picture from the Omi Art Center in Columbia County, NY.

The wanton cruelty shown by the heartless enslavement of rocks is almost too much to bear for a geologist like myself.

Happy Imbolc

February 2, 2010 is a Cross-Quarter Day – it’s the half-way point between the Winter Solstice, which occurred at December 21, 2009 at 17:47 UTC and the Vernal or Spring Equinox which will occur on March 20, 2010 at 17:32 UTC. The exact midpoint, by my calculations, is actually at 40 minutes after midnight on February 3 local time (EST).

Many ancient cultures celebrated this day since it has an astronomical basis and, in Europe, is often taken as the beginning of spring. On the traditional Celtic calendar it’s called Imbolc and celebrated the goddess Brigid. On the Christian calendar, this is supplanted by St. Brigid’s Day after one of Ireland’s patron saints. Another Christian holiday, Candlemas, or the Feast of Presentation of Jesus at the Temple, also occurs at this time in February and is based on the Gospel account in Luke 2:22-40.

In the secular world, we have Groundhog Day, developed in Pennsylvania during the 18th century by German immigrants. It appears to have its roots in European weather lore but there a badger or a bear was the forecaster. Also, some people see ties to Imbolc since that Celtic holiday is also traditionally associated with weather prognostication.

Whatever you celebrate, we can all enjoy the fact that we’re half-way to the to the first official day of spring!

Interesting math column

Steven Strogatz, a Cornell math professor, will be writing a blog for the New York Times about mathematics.  As he puts it:

Crazy as it sounds, over the next several weeks ... I’ll be writing about the elements of mathematics, from pre-school to grad school, for anyone out there who’d like to have a second chance at the subject — but this time from an adult perspective. It’s not intended to be remedial. The goal is to give you a better feeling for what math is all about and why it’s so enthralling to those who get it.

Sounds interesting.  Here's the first installment - From Fish to Infinity.  I look forward to reading the next.