The amount of useful recreational boating information that can be found on the World Wide Web never ceases to amaze me. Just this past week I found several new sites that have some incredibly valuable information, all for free by simply clicking a mouse.

Take for example the National Imagery and Mapping Agency (NIMA).

I’d bet that a lot of my readers don’t immediately associate this government agency with a large amount of nautical information.

But you should! NIMA’s capability for providing great data from online: U.S. Notice to Mariners, to navigation calculators, to the International Code of Signals, and the Light Lists is truly impressive. This is one web site that the full spectrum of boaters, from salty mariners to the newest boat owner will find very useful!

Lets look at the Nautical calculator section of the web site.

First, go to the following web address:

http://164.214.12.145/calc/calc_options.html.

There are some major sub titles (subject areas) that come up:

— Celestial Navigation

— Conversion Calculator

— Distance Calculator

— Time Measurements

— Weather Data Conversion Calculator

— Sailing Calculator

Different commercially offered programs do utilize all these programs; however, these are FREE!

What specifically is available? Well, for those mariners that still do your own sight reductions for celestial navigation this program will provide the compass error from amplitudes observed on the celestial horizon.

For conversions you can automatically go from meters, to feet and then to fathoms. Under time measurement the program will automatically convert between time zones. If you need weather data this program will convert from Fahrenheit to Celsius and back again. Finally if you need detailed sailing information this web site will help you with Great Circle or Mercater calculations.

The National Imagery and Mapping Agency, one government agency with a lot to offer the boating public. Next week we will continue our look at this great FREE web site and the areas that are offered to you, the general public.

Until next week, remember to boat safe, boat smart and since it so darn hot, drink two extra glasses of water!

LCDR Joe DiRenzo is a resident of Suffolk and a regular News-Herald columnist.