Monthly Archives: February 2016

The Bounty Mutiny and the Pitcairn Island Position Error

Posted on 5-February-2016 by mathscinotes

I liked reading the book Longitude by Dava Sobel and I also enjoyed the television movie version. I was recently doing some reading about the Bounty mutiny when I realized that the problem of measuring longitude played a role in that tale as well. The story of longitude is one of technology and obsession. While mariners had been able to measure their latitude accurately for centuries, measuring one's longitude required the development of accurate timepieces. Longitude is the story of the development of the marine chronometer. In essence, our modern GPS systems are extremely accurate clocks that provide the ultimate realization of the longitude goal. Continue reading →

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Remakes Improving The "Robinson Crusoe on Mars" Theme

Posted on 3-February-2016 by mathscinotes

I just watched the movie The Martian with my oldest son, and I really enjoyed it (Figure 1). As I thought about the movie, it certainly was the best of the "man versus Mars" movies I have seen – and it was the first with a real sense of humor. Every so often, Hollywood rediscovers the escape from Mars theme and The Martian was the best of this genre yet. Continue reading →

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Estimating The Lifetime of an Electrolytic Capacitor

Posted on 2-February-2016 by mathscinotes

Our optical products are powered by AC power converters (e.g. wall adapters, uninterruptible power sources) that we buy from outside sources. Over the last two weeks, I have been dealing with a number of aluminum electrolytic capacitor failures in these power products. Like all components, electrolytic capacitors eventually do wear-out (e.g. Figure 1). Unfortunately, their lives are relatively short (~15 years) compared to other components in the system. We have had some of these power sources in the field for nearly ten years, so we are starting to see some worn-out capacitors. Continue reading →

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