Cool Stuff

I always enjoy learning cool stuff. One of my favorites has always been using the sun and you wrist watch to find true north. Of course that only works for local time, i.e., your local time zone, so it's not much help offshore.

However, I just learned a great way to tell time anywhere in the northern hemisphere at night. All you need to know is the current month. Basically, you use the big dipper as the hour hand on a 24 hour clock, which turns backwards, and adjust it based on the current month. If you're interested in how it works, take a look at this page:

http://www.johnpratt.com/items/astronomy/telltime.html

and if you'd like to see and read about an instrument invented during the Renaissance to help do the calculations automatically, take a look at this:

http://en.m.wikipedia.org/wiki/Nocturnal_(instrument)