Quick Answer
The Plough can be used to help navigate without other celestial aids, particularly in the northern hemisphere. It's a recognizable asterism that can be used as a reference point to locate other stars and constellations. As a result, it can be an effective aid for navigation in certain situations.
Understanding The Plough
The Plough, also known as Ursa Major, is a prominent asterism in the northern sky. It consists of seven bright stars that form a distinctive shape, often referred to as the “Big Dipper”. To use The Plough for navigation, locate the two stars at the end of the “bowl” that make up the asterism. These stars, known as the “pointer stars”, are aligned with the North Star, Polaris.
Locating The North Star
To find Polaris using The Plough, extend an imaginary line through the pointer stars. Continue this line for approximately 30 degrees, or the width of your fist held at arm’s length. The North Star should be visible in the direction of this line. Polaris is a relatively bright star, but it’s also a slow-moving star, making it a reliable navigation aid.
Using The Plough in the Field
When navigating in the field with only The Plough as a reference, it’s essential to be aware of the time of year and the position of the asterism in the sky. As the Earth rotates, The Plough appears to move across the sky, but its position relative to other stars remains relatively constant. Use The Plough to locate Polaris, and then use Polaris to estimate your direction of travel. With practice and patience, you can use The Plough as a reliable aid for navigation in the northern hemisphere.
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