They say there’s no school like the old school, and nowhere is that truer than celestial navigation. Even as newer technologies have streamlined sailing, this method of calculating one’s position and journey is still standard education for many yachtsman and navy recruits. If the idea of traversing the seas with centuries old methods appeals to you, then here’s our beginner’s guide to celestial navigation, and our most recommended reading material.

Celestial Navigation explained

To successfully navigate at sea requires two key things - your eyes, and a celestial body. The sun is most often used, but the moon, stars and planets work well too. The basic principle is to calculate the angular measurements (known better as sights) between the celestial body and the visible horizon. This lets you locate your precise position on the globe, regardless of whether you’re on land or sea. You need specific tools for practical celestial navigation, including a...

  • Marine chronometer - A highly precise time-piece that can be used to measure longitude
  • Sextant or Octant - Used to measure the distance between the celestial body and horizon, via ‘star telescope’.
  • Almanac - An annually updated publication that lists schedules of the coordinates of celestial objects
  • Sight reduction tables - these help perform the height and azimuth computations,
  • Nautical charts - ‘Sea maps’ of your particular region
Why not just use a GPS navigator?

The development of electronic navigational charts and the computer programs designed they’re work with is nothing to sneeze at, but sailing as a profession, sport and hobby would not be the same if we relied solely on technology. As researchers have argued, the high level of knowledge we must acquire to navigate around landmarks and locations still proves more efficiency than our interaction with GPS software, on a cognitive level. We tend to build a deep semantic knowledge of the place we’re sailing through, and electronic guides (no matter how accurate they may be) cannot always offer fast and accurate enough instructions.

Even if we ignore the obvious arguments (i.e. what if the technology fails, or some uploaded celestial data is incorrect), relying on GPS navigators degrade our map reading, sight taking and path planning skills - similar to how relying on a calculator erodes your ability to do simple arithmetic.

As technological solutions rely more on the internet and communication, they’re also open to more novel threats. For example, last year the U.S. Naval Academy reintroduced celestial navigation into its teaching course after nearly 30 years of satellite technology training. The reason? The escalation of hacking threats...

Recommended reading on celestial navigation

The RYA Navigation handbook: This certified reference guide for the RYA Day Skipper and Yachtmaster Offshore courses, this book covers all traditional navigation techniques to the exam syllabus standard.

Wiley Nautical Celestial Navigation: If you need a primer on traditional navigation techniques, this book provides a solid grounding. It begins with a foundation on the basic concepts and definitions we mentioned, and then moves on to how to use the all-important sextant.

Reeds Maritime Meteorology: This guide is written primarily for the use of serving and training deck officers in merchant ships, as well as fishermen. Covers all aspects of maritime meteorology in a comprehensive, and highly valuable guide.

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Post By Nicole Sage