Monthly Archives: October 2006

An Alien Sky?

The Astronomy Picture of the Day web site highlighted this photo today of what looks like a daytime sky from another planet.

It was actually taken of our daytime sky using a small refracting telescope; The small crescent is Venus, and the larger one is the moon. Click on the image to see a higher resolution version, and find all the details on how the image was taken here.
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Filed under Astronomy

More Solar Wind Shows

Space Weather had an excellent photo of the auroras over Nuuk Greenland when the solar winds hit the earth’s magnetosphere last night.

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A Snowflake Closeup

I first found this image on Chet Ramo’s Science Musings blog, and just stopped to look at it for a while. (click on the image to view a high resolution version.)

At first glance, it doesn’t really look like a snowflake. In actuality, it is an image of several snowflakes of differing conformation (I counted about eight different varieties) that have been sputter coated with platinum at a very low temperature (in order to make them conductive) and then imaged with a Scanning Electron Microscope equipped with a low temperature stage. The resulting gray-scale image formed by the electron beam was then digitally colored just as the old black and white movies have been “colorized” to result in the above “false color” image. Here’s a picture of the specific unit that was used to take this image.

Hitachi S-4100 field emission Scanning Electron Microscope

Check out more details on the equipment here, and the original source of the snowflake crystals images here, and here.

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Filed under Computer Science, Graphics, Technology

A Stellar Explosion in Progress

Check out the latest Hubble photo showing the same stellar explosion from V838, Monocerotis and its evolution since 2005.

https://i1.wp.com/imgsrc.hubblesite.org/hu/db/2006/50/images/a/formats/web_print.jpg

From the Hubble Web site: “These are the most recent NASA Hubble Space Telescope views of an unusual phenomenon in space called a light echo. Light from a star that erupted nearly five years ago continues propagating outward through a cloud of dust surrounding the star. The light reflects or “echoes” off the dust and then travels to Earth.

Because of the extra distance the scattered light travels, it reaches the Earth long after the light from the stellar outburst itself. Therefore, a light echo is an analog of a sound echo produced, for example, when sound from an Alpine yodeler echoes off of the surrounding mountainsides.

The echo comes from the unusual variable star V838 Monocerotis (V838 Mon), located 20,000 light-years away on the periphery of our Galaxy. In early 2002, V838 Mon increased in brightness temporarily to become 600,000 times brighter than our Sun. The reason for the eruption is still unclear.

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A Great Intro Electronics and Robotics Project

The Make Magazine web site pointed me to this great open house activity that the Electrical Engineering department over at WUSTL put on for potential incoming freshmen. Students could show up and build their own light-activated robot with a few dollars worth of parts in about 30 minutes using absolutely no tools whatsoever. And they got to take their new pet home when they were finished with version 1.0.

Using the paint roller drive wheel vs. motor shaft ratio of diameters as an effective gear reduction is a bit of creative genius. Given that there are only ten or so parts and the instructions are only a page long, I’m thinking this one could be useful even in late elementary school.

Some early prep work was necessary to hot-glue the breadboards to the paint rollers, and perhaps solder the connectors onto the battery leads. But intrepid students could easily figure that part out for a longer classroom activity. I just love this photo from the web site of one student “walking their robot” and leading it with a flashlight.

Get the one-page assembly instructions here and get those kids building robots. Once they’ve mastered this initial version, begin asking questions like, “okay, now how would you build another version that steers?” or “How would you make it go faster, or climb steeper hills?” or “how big could you make it and how much would it carry?”

What a great beginning.

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Diet For Energy Independence

In a paper scheduled to appear in the Engineering Economist, Laura McLay and Sheldon Jacobsen have determined that growing obesity across the US is imposing even more of an economic impact than the often-reported health care costs of treating its side effects such as type 2 Diabetes.

It should come as no surprise to anyone with any Physics background at all that it takes more energy to move more mass around.

“The obesity rate among U.S. adults doubled from 1987 to 2003, from about 15% to more than 30%. Also, the average weight for American men was 191 pounds in 2002 and 164 pounds for women, about 25 pounds heavier than in 1960, government figures show.”

Using those weight figured combined with statistics on 2003 driving habits, it is pretty straightforward to conclude that about 39 million gallons of additional fuel are used each year for every pound of average weight increase across the US.

So relative to our svelte 1960 profiles, at a gas price of $3.00 per gallon the US is consuming around an extra $3 billion of oil for automotive fuel a year simply because we are getting fatter. And then there’s the issue of airline fuel costs as well, an effect already reported by the CDC.

So if we could just manage to curb our waistlines, we can decrease our dependence on foreign oil. Maybe we could even manage it by driving less and walking more. What a virtuous cycle that would be.

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Filed under Health, Math

The Economic Value of Education

A government report based on data from the Census Bureau has determined that a bachelor’s degree is worth about $23,000 a year, with college graduates earning and average of $51,554 in 2004 compared with $28,645 for those with only a high school diploma. If you carry that yearly salary difference through retirement age, you end up with a total difference of about $1.2M.

High School dropouts earned an average of $19,169 a year, and those with advanced college degrees earned an average of $78,093.

So high school is worth about $502,000

College is worth an incremental $1.2M

Graduate school is worth another $1.4M

It seems like a no-brainer to me, specially when you consider some of my buddies who have turned what they learned into economic engines worth billions of dollars as an up-side. Of course there is a down side, but according to the large-scale statistics, even Joe-average is best served staying in school a little longer.

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