Introduction: How to Find 'Polaris' - the North Star
Polaris, the North Star, is an important navigational star because its position in the sky is almost exactly (within a few degrees) lined up with the rotational axis of the Earth. This means that no matter where you are on the Earth (so long as you're in the Northern Hemisphere) if you face toward Polaris you are facing North. Finding Polaris is an incredibly useful night time navigation technique that's helped everyone from the Egyptians to the Vikings find there way on the open seas. But it also is one of the easiest stars to find - something my Dad taught us as kids - and can serve as a great entryway into the world of star gazing and constellations. In fact, locating it involves two of perhaps the three most recognizable constellations in the northern hemisphere (two of which we'll mention in a second; the third being Orion, the hunter).
Let's get started.
**Note** All photos in this instructable were found on the internet, and are the property of their respective owners. I will cite as much information about original sources as I can find. [I wanted to take the photos myself, but unfortunately the rainy season in Japan could just as well be named the cloudy season. (;_;) ]
**Apology**Sorry for the poor quality of some of these photos. It turns out star fields don't hold up well under the Instructables.com image compression. Feel free to click the [ î ] in the upper left corner to view the full size images if you're having trouble.
Step 1: Locate the Big Dipper - (Ursa Major)
The first step is to find the constellation of Ursa Major, commonly known as the Big Dipper. It is perhaps the most easily recognizable constellation in the night sky, and looks like a large spoon or perhaps a wheel barrow.
It is composed of seven bright stars - three in the handle and four in the head of the spoon. If you can find it in the picture above, great. If not, look at the next photo.
Step 2: Trace a Line to the North Star
Next, imagine the line connecting the two front stars of the Big Dipper, which I've marked in red. If you continue this line off to the upper right, the first bright star you come to is Polaris, the North Star.
Step 3: Checking That It Really Is the North Star
But with the North Star being such an important and useful star, you want to be sure you've got the right one. After all, there are a lot of stars up there, and they do all look pretty similar.
Luckily, not only is Polaris in line with two stars from the Big Dipper, it is in fact a part of the Little Dipper itself, which makes it easy to check if you're looking at the right star. Like the Big Dipper, the Little Dipper (Ursa Minor) is composed of seven stars, three in the handle and four in the head of the spoon (marked in red). The Little Dipper floats above its bigger brother, and is angled as if it were pouring water into the larger spoon. Polaris is the last star in the handle of the Little Dipper.
If you can recognize and identify the relationships between these 14 stars, you will always be able to find the North Star. It helps that they are some of the brightest stars in the night sky.
Step 4: Test Your Skills
Of course the best way to test your new found star-gazing abilities would be to go outside in the country and take a look at the heavens. But if that's a bit unfeasible at the moment, then try your hand at finding the North Star in these next two photographs. The first is rather easy, the second is maybe challenging.
The answers are given in the second and fourth photos.
If you're a person whose known this simple trick for years, then I hope this instructable will inspire you to share your knowledge with others. If you're a person whose never looked at the stars before, then I hope this piques your interest in the night sky. And if you're a person who is inexplicably lost in the wilderness but somehow has a wi-fi connection and decided to check instructables.com for guidance, than I hope this helps you find your way to civilization.
Happy star gazing!
Participated in the
Celestron Space Challenge