January 30, 2023


Information Technology by cobuman

Constellations, the ancient GPS

If you got lost at night and don’t have a map, looking to the stars may not be your first instinct, however, that was exactly how sea-faring explorers used to do it. Based off of major constellations and their placement in the sky, the stars acted as an early age GPS, with different constellations and star patterns occurring in different parts of the globe.

In the Northern Hemisphere, these are the northern constellations of Cassiopeia and the Big Dipper, whilst in the Southern Hemisphere, the Southern Cross (Crux) and Centaurus constellations. Along with other major arrangements, you can easily direct yourself in the dark, or ensure you are on the right course. Additionally, using the lunar cycle and good sense of direction will help you even more.

Cassiopeia; source wikimedia.org; author Till Credner
Big Dipper (ThePlough)
Big Dipper (ThePlough); source wikimedia.org; author Maxiesnax
Constellation Crux
Constellation Crux; source wikimedia.org; author Till Credner
Centaurus; source wikimedia.org; author Till Credner

By knowing the constellations, their location relative to the North Star and you current location as well as the rough direction of your destination, you will be able to determine which bearing you should take and for how long. If this doesn’t sound 100% accurate, it is because it isn’t.

Like anything, navigating using the stars was a skill that needed practice, knowledge and a good dose of luck, navigators on cargo ships and exploration vessels needed to be good at their jobs in order to get their ships from point A to point B. That being said, misjudging and misreading the stars was common even amongst seasoned navigators, but never by excessively large margins.

sextant; tool used for ship navigation
sextant; tool used for ship navigation

One of the reasons leading to the discovery of Australia was Dutch merchantmen travelling the spice road overshooting their turn mark after passing the Cape of Good Hope and sailing alongside the western coastline of the country. However, using the stars as a navigation technique was around long before the European nations set sail around the world.

Early Polynesian explorers, the Lapita (1600 BCE – 500 BCE), were some of the first to recognize the use of stars as a way of locating oneself. This led them to colonize and populate large swathes of island groups across the Pacific Ocean from Papua New Guinea to Samoa. Likewise, the Vikings also used the stars to help guide them.

Map Location of Lapita Culture; source wikimedia.org. ; author Christophe cagé

Both these people were renowned as incredible sea-farers, no doubt thanks to their ability to read the constellations and determine their location with enough accuracy to continue their voyages. Although through advances in technology and the prevalence of maps, we no longer need to know the constellations and how to read the stars, but it certainly doesn’t hurt!