Sailing by Starlight: the lost art of celestial navigation

Posted on By Andrew Thaler 12 Comments on Sailing by Starlight: the lost art of celestial navigation
Science

This post is a slightly modified transcript of a talk I gave on celestial navigation. As some of you know, I like to build things, and I recently decided to build some classic navigational tools. Of course, in the process of building these instruments, I had to learn how they work. The history of celestial navigation is fascinating and deeply connected to the history of astronomy and mathematics. The original slide show can be found at the bottom of this post. Enjoy!

I’m going to begin with a seemingly simple question, then hopefully give you some basic tools to answer that question. Where are you?

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Finding Melville’s Whale: Chapter 14 – Nantucket

Posted on By Andrew Thaler
Uncategorized

Chapter 14 of Herman Melville’s classic – Moby Dick. Read along with us and discuss this chapter or the book as a whole in the comments. Nantucket At last the two arrive in Nantucket. Nothing but sand and the whalers’ resolve. No timber nor weeds, everything that built this island was brought by men that … Read More “Finding Melville’s Whale: Chapter 14 – Nantucket” »

Compact Fluorescent Lights, Energy, and Mercury

Posted on By Andrew Thaler 38 Comments on Compact Fluorescent Lights, Energy, and Mercury
Conservation, Science

We recieved several responses to Dave’s post this week on the bizarre “Save the Light Bulb” movement. A movement that seeks to ban energy efficient compact fluorescent lights (CFL) and return to the old, energy expensive, incandescent bulbs. The primary critique is that CFL’s contain mercury, and thus, any environmental benefit is negated by mercury exposure when the bulbs break or are thrown out.

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What species of skate is for dinner? New research challenges elasmobranch fisheries policy

Posted on By David Shiffman 7 Comments on What species of skate is for dinner? New research challenges elasmobranch fisheries policy
Conservation, Science

I write a lot about shark conservation issues, but I rarely focus on their fellow elasmobranchs. Rays and skates have similar life history strategies as sharks, and many species are similarly overfished.  A friend just sent me a cool paper about the conservation of skates, which provides an excellent opportunity to remedy this oversight.

A major issue standing between well-managed elasmobranch fisheries and the mess we find ourselves in today is species identification. Many species look very similar (in some cases, DNA tests are required to tell them apart), which makes recording catch statistics extremely difficult. In fact, United States fishery management policy sometimes focuses on  species complexes (i.e. “Large Coastal Sharks”) of sharks rather than individual species. Species identification is a major issue for skates as well.

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Vignette from the Anthropology of Knowledge: Cree Hunting

Posted on By Amy Freitag
Science

Scientific knowledge comes in many forms, some not explicitly science. Social scientists call this “ways of knowing” – you can think of it as a framework on which you hang the specifics as you learn them. The framework is set up early in life and historically, scientific knowledge was held within a religious ‘way of … Read More “Vignette from the Anthropology of Knowledge: Cree Hunting” »