How does the North Star always point north?

The north star, also known as Polaris, can always be found pointing north but how is this when the Earth is constantly rotating? If you took a long exposure photo you would see a similar thing to the picture above. All the other stars look like they are rotating around Polaris but this is just caused by our movement.

It just so happens that Polaris lies on the same axis as the Earth and this means that when the Earth rotates, the star doesn’t look as though it is moving at all.earth-23592_960_720.png

So this is kinda cool, right? If you’re ever lost (and above the equator) then you can look to find the north star. Although, I’m pretty sure google maps will be a quicker way of finding out where you are.

Polaris is actually built up of three stars which are called Polaris B, Polaris Ab and Polaris A but from Earth we see these as one star. Lots of people say its the brightest star in the sky but this is a misconception. It’s about the 50th brightest star but is still quite easy to find.

Untitled 1

First you need to locate Ursa Minor (AKA Little Dipper or Little Bear – that last one is a stretch on the imagination) Polaris is located as pictured to the left.

Take a good look at the sky and be careful not to mistake Ursa Minor for Ursa Major.

This is a screenshot from a program called Stellarium which is free to download and contains a map of the night sky. It is a good program for getting used to where the stars are positioned before heading out into the cold.

 

 

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s