Navigation is as easy as it’s ever been. With the existence of technologies such as GPS (global positioning system), it’s hard to get lost, especially off the beaten path. Furthermore, companies such as CAST Navigation are helping take GPS technology to whole new levels of reliability and efficiency.
Now, ask yourself this: what if GPS was never invented? You might think it’s impossible to find your way (not a lot of people are familiar with using a compass, for one). However, you only need to look at the past. The world would’ve never been opened up to all if it was impossible.
Astronomy is perhaps the principal component of navigation before GPS. Henry Neeley, a lecturer at Hayden Planetarium in New York in the 1950s, is famous for claiming that celestial bodies can be used for navigation despite the existence of GPS. He is right in certain ways. Unless the technology can be designed for full infallibility, the stars in the night and day skies are as reliable as they can be, for they’re all fixed points.
Astronomers identify 57 individual stars that navigators can use to triangulate their positions. These stars are chosen because they shine brighter than all others in the night sky. Their wide spacing also makes it easier to identify them. A navigator must determine the altitude of a star above the horizon. Once he does, he finds out his so-called ‘circle of position.’ He then must go on to measure the altitudes of other stars to know where these points intersect, which is an approximate position on the globe.
Ancient civilization used various tools while using the stars to navigate. One good example would be the Vikings. While sailing the oceans, Viking navigators would use sundials to triangulate their location. They rely on the closest star. Sundial usage for navigation is perfectly demonstrated by the historical TV series Vikings, in which the lead character Ragnar Lodbrok sailed west to England in search of plunder.
But what if it was cloudy? Vikings have an answer in the form of crystal known as a sunstone. A team onboard the Swedish vessel Oden tested this theory and found that by looking at the sky through the sunstone, the sundial can be lit. Crystals work as filters with changing colors and brightness while pinpointing the angle of sunlight. With the help of the sun (and the Sunstone), the Vikings are arguably history’s most successful navigators before GPS.