wrote

I was just told by a friend that I should learn celestial
navigation before sailing around the world because
GPS devices don't work that well in the middle of the
ocean and can malfunction if they get wet, etc.

Does my friend have a point even if I intend to bring
3 independent GPS systems with me ?

How about if I just get a cheap sextant and the book
"Celestial Navigation When Your GPS Fails" and
bring them with me ?

The information supplied by your friend perhaps could use some updating.

The basic GPS system is very reliable and is used worldwide by many,
including the aviation industry.

Small, battery operated units, likely to be found on small boats are more
likely to fail than those on aircraft; however, having multiple back up
units on board addresses this issue.

Being able to use a low cost sextant as the last opportunity navigation
device, certainly has it's advantages, and basic celestial navigation is not
difficult to learn.

SFWIW, I have a new, still in the box, Davis, Mark15 sextant, complete with
artificial horizon that I'm about to put on Craig's list.

If you are interested, contact me off list.

Lew