30 August 2009

Mt. Wilson Observatory threatned by fire

The Mount Wilson Observatory is home to the 100-inch (2.5m) Hooker telescope, one of the most historical telescopes in the era of modern astronomy. Following on the heels of the Harvard College Observatory Computers'1 work on classifying stars, the Henry Norris Russell used the Hooker telescope, and in conjunction with Ejnar Hertzsprung developed the diagram now known as the Hertzsprung-Russell (or HR) diagram, a diagram of as much importance to astronomy as the periodic table is to chemistry. More famously, Edwin Hubble used the Hooker when he discovered the expansion of the universe, disproving the leading steady state hypothesis (even espoused by Albert Einstein). It is probably even more important that Hubble first proved that all those fuzzy "spiral nebulae" were actually entirely separate galaxies, but we take that for granted today, while cosmologists are still working on the details of the universe's expansion.

So with this background about the Mt. Wilson Observatory under your belt, perhaps you will understand some of the fear I feel when I read that as of 5:42 PDT (8:42 EDT) the LA Times was estimating that the current wildfires outside LA would probably raze the observatory within hours. As of this writing (8:57 PDT / 11:57 EDT) the fires have not yet reached the observatory (though they are visible from the observatory webcam, link is to a screenshot of the webcam since the webcam server itself is overloaded). The director of the observatory reports that firefighters will be remaining in place on Mt. Wilson overnight, implying that it is safe enough to do so, and hopefully they will be able to keep fighting and save the historic observatory.

If you the most more up-to-date information that I have been able to find, follow Mike Brown's twitter feed @plutokiller (yes, THAT Mike Brown). If the observatory does burn down overnight, I'd appreciate it if someone txted me.

1 Also referred to as "Pickering's Harem,"2 after the fact that Harvard College Observatory Director, Edward Pickering, famously stated that his male graduate students were so inept that his maid could do a better. Following on the statement, Pickering did hire his maid (Williamina Fleming) and then a string of other women, hence the unflattering name for the group. Despite the name, these human "computers" did amazing work, revolutionizing the field of stellar classification.

2 The incidence of referring to both harems and hookers in the same post is purely coincidental.

Current music: "Cold Missouri Waters" by Dar Williams, et al.

25 August 2009

Noble Nobels

During WWII, two German Nobel Prize laureates (in physics) escaped to Denmark. When it too was taken over, their medals were chemically dissolved by Danish physicist Neils Bohr and Hungarian chemist George de Hevesy to keep them safe from the Nazis (and to keep the physicists safe as well, as taking gold out of Nazi Germany was a crime). The solution must have just looked like any other bottle of chemicals, because after the war was over, Hevesy precipitated the gold out of the solution, sent it back to the Swedish institution that grants the Nobels, and they generously recast the medals and reawarded them to the two physicists.

02 August 2009

Order of Magnitude

This image is truncated on the right, please click on it to see the full version!

With the power of science we can now calculate this! At least a rough number.

Let's say that teach morning you create a small bit of crud 1mm to a side, so 1mm by 1mm by 1mm, so the volume of this one bit of crud is 1e-9m^3 (or if you like to write things fancy, 10-9m3). Yeah you have two eyes, but this is a rough calculation, so I'm going to ignore that. I'm also going to ignore that you don't wake up with crud every day of your life. We do however need your lifespan, let's say 80 years approximately, 365.25 days per year, so you live 2.922e4 days, or let's round that off and say 3e4 days. Multiply the number of days you wake up, by how much crud you get each day, and voila, 3e-5m^3.

According to my favorite conversion website, a teaspoon has a volume of around 5e-6m^3, with the result that you actually produce around 6 teaspoons of eye crud in your lifetime.