Just Passing on a Recommendation

I have been seeing a lot of posts trickling out of the page Compound Interest lately.  It has wonderful, clean, crisp, and succinct explanations for many chemical phenomenon.  You should definitely check them out: Compound Interest

Here is some of their work to tempt you to go visit!

The Power of Observation

Eye of the Beholder:

Take a look at the pictures below:

http://www.nature.nps.gov/night/yoursky.cfm

The pictures above are the same night sky with filters to show what it would be like in a urban, suburban, and dark-rural environment.  What you can experience with your senses has been the standard for observation for millenia.  The pictures above demonstrate that observation depends greatly on your environment.  It is believed that two-thirds of humans on earth cannot easily observe the milky-way due to the light pollution from urban settings. In the first picture, you could only see 500 stars in the night sky, while in the third picture, you would be able to see nearly 15,000!

Imagine if the chronology of discovery had been reversed and we had the light pollution before we had the telescopes to see space well.  Sure, we would have probably seen the usual heavenly bodies observable to the visible eye (Saturn and Venus are pretty bright and discovered in the 1500s), but it would have taken us much longer to discover other planets such as Uranus and Neptune, whose discovery came centuries after that of the other gas giants (1781 for Uranus and 1846 for Neptune).

More than Meets the Eye:

One of the beauties of modern science is that we have developed ways to augment our senses.  This has opened up observation that was formerly not available to us.  Our eye can see objects approximately 0.1 milimeter wide.  This is the scale of a human hair.  With modern microscopy, we can see objects around the 0.1 nanometer scale.  That is a difference of 1000000 times.  For perspective, a human hair 1000000 bigger would be the wider than a football field.  Your eye cannot see bacteria, cells, molecules, etc.  There is a whole world of invisible things without technology.  For one of the best perspectives on scale, please check out this page which puts the entire universe to scale.

Recently a friend told me this quote that she attributed to W. B Yeats, "The world is full of magic things, patiently waiting for our senses to grow sharper"  A scientist might change that quote to, "The world is full of magic things, patiently waiting for our instruments to grow more sensitive."  Either way it is an excellent quote.

Take a look at this video, it shows how the scale of structures can influence color. The video is a bit "energetic", but it explains it well.


Butterfly Blues from NISE Network on Vimeo

It Doesn't Always Take a Sixth Sense:

The technology is great, and these sensitive observations have opened our world to microprocessors, drug delivery, solar energy harvesting, and many other modern technologies.  Sometimes it is important to remember that our basic senses are incredibly sensitive given the chance.

Smell:

Everyone knows that a gas leak is characterized by a rotten egg smell; however, it is not the gas that smells. Gas companies add mercaptans or sulfur containing molecules to the gas stream, often ethane thiol.  Your nose is sensitive to this molecule in the parts per billion (ppb) range.  If as much as 3 molecules (yes three) were present in the volume of air that can fit in a beach ball, your nose could detect it.  Now that is a great chemical sensor.

Hearing:

The human ear can detect sounds from roughly 20 Hz to 20 kHz.  Though that is not the widest range in the animal kingdom, it is pretty amazing to think that a bunch of little hairs, a thin mebrane, and some tiny bones can measure sounds of that many frequencies.

Taste:

Your tongue is a chemical sensor all to itself.  The taste of sour, sweet, salty, etc. stems from chemical reactions at your tastebuds.  Bitter is commonly an acid base reaction between the components in the food.  For instance, citric acid in lemons will give a sour or tart taste.  That is because the molecule can donate a proton (hydrogen atom without electrons) to your taste receptors.  In fact, a fruit fondly termed "miracle berry" has a protein that when activated by acids actually binds to the sweet receptors on your tounge.  If you eat a lemon, it does not taste sour, it tastes sweet.  That is not a miracle, it is a sweet chemical reaction!

Touch:

Touch is perhaps one of the least sensitive of the senses.  It relies on nerve endings in the skin which do not have the same density or spacing on all parts of the body.  It should be noted that if the temperature change is quick, the fingers can perceive less than 0.2 degree C changes in temperature.  Cold and hot differing because of different receptors.


This thermal sensitivity, in fact, just solved a persistent puzzle in our laboratory.  A student noticed a sample warming up before going to analyze it.  When she switched to a different solvent, it did not warm.  Upon analyzing the samples, the one that did not warm was the desired product.  By pure coincidence, the sample that warmed had reacted with the solvent to produce the intermediate in the reaction!  We had been wondering why the reaction was stopping at the intermediate and not going to completion. As it turns out, it was reverting from product to the intermediate in the sample vial.  All of the material we thought was junk for the last several months was actually the desired product, just waiting for someone to notice that the temperature was changing. 

The combination of the basic sense of touch, a sophisticated instrument to measure radio frequencies of atoms, a little bit of luck, and some good old common sense has us back in the business of making new molecules!  Now that is the Power of Observation!


Here are a few of the references I linked to above:

http://www.nature.nps.gov/night/yoursky.cfm

http://science1.nasa.gov/science-news/science-at-nasa/2001/ast01nov_1/

http://vimeo.com/42373587

http://en.wikipedia.org/wiki/Hearing_range

http://en.wikipedia.org/wiki/Synsepalum_dulcificum

http://www.scholarpedia.org/article/Thermal_touch