The above photo was taken using a technique we published in a story titled “Shipboard Digital Camera Tricks“. Many more great moon pictures by the photographer, Licya, can be found HERE.

by Miranda Max

Sailors and captains have been using the moon to navigate the sea for ages. The history between the moon and the sea is deep and rich. We find the relationship even in literature, as in Emily Dickinson’s The Moon is Distant from the Sea.

The moon is distant from the sea,
And yet with amber hands
She leads him, docile as a boy,
Along appointed sands.

He never misses a degree;
Obedient to her eye,
He comes just so far toward the town,
Just so far goes away.

Oh, Signor, thine the amber hand,
And mine the distant sea, –
Obedient to the least command
Thine eyes impose on me.

Celestial navigation, also known as astronavigation, has evolved over several thousand years. Throughout this time the moon has helped sailors cross oceans without having to rely on estimated calculations and physical features. While the sun may be the easiest and most commonly used natural compass, the moon works just as well for the skilled navigator.

Angular measurements, when taken between celestial bodies in the sky and the visible horizon, are used to locate one’s position on land or at sea. Any celestial body is located directly over only one specific geographic point at all times. This location can be described by latitude and longitude and is known as the celestial body’s “GP”. From here, the precise location of a ship at sea can be determined by referring to the Nautical or Air Almanac, locating that exact second of time, for that calendar year.

Today the U.S. Navy and U.S. Air Force continue to instruct sailors and aviators on the moon and its use in determining your position. Using the moon for navigation has many benefits, such as its ability to be used independently of ground aids, its global coverage, its constant availability despite occasional cloud coverage, and the fact that it is much larger and easier to recognize than stars and planets.

If it weren’t for the relationship between the moon and tides, navigation wouldn’t be possible. A significant gravitational pull exists between the earth and the moon. This pull causes tides in the ocean to occur. As the moon’s gravity pulls the earth and water towards it, the water moves to the side of the earth that faces the moon. At this same instant, another force pulls the water in the opposite direction because of inertia. Furthermore, these two opposing forces are equal to each other, and are always simultaneously moving toward and away from the moon.

Navigating by moon is accomplished relatively easily using the celestial navigation tables and a sextant. Today we keep alive a rich history of ocean navigation through photos and old stories, calling to mind the images of ships from long ago and sailors who never miss a degree, obedient to the moon as their captain.

MaritimeLinks.net (a must see site) brings us what is reportedly “The Worlds Sexiest Sextant” or less smashingly called the Cassens & Plath Horizon Ultra. Why? Here’s their answer:

WIRED magazine ran an article that was a real surprise to me: It was about a sextant, and a very good looking sextant at that! This old school navigational device has some sexy styling that any nautical buff would be proud to get their hands on. Take a look at the story and the picture of this excellent piece of retro nautical tech. Read More

Wired’s Take:

Like any good sextant, this $1,500 model measures the angle between the horizon and the sun, moon, or other celestial body, which helps you determine your coordinates to within a mile. What makes the Horizon Ultra stand out are its finishing touches: a brass-alloy frame to resist warping, a white enamel coating to deflect heat, and a lighted micro meter for judging angles at dawn or dusk. Just think how nice it’ll look next to your titanium and carbon-fiber abacus.

Related Links:

• Purchase your own
  
• Wired Article
• Manufacturer’s Page

Todays gCaptain tip is a simple link to a simple slideshow that teaches you star identification the night sky.

QuiteBay’s: The Night Sky
(thanks to Lifehacker for the tip)

Also…not very instructional but still interesting: 1822 Celestial Atlas