In the days before a GPS, many explorers relied on the North Star to aid them with navigation. The North Star, which is actually known as Ursae Minoris or Polaris, is a star that is positioned in such a way so that it moves very little from the perspective of people on Earth.

While it was once thought to be completely stable by many people, it is now known that this star actually moves around a circle in our sky over the course of a 24,000-year cycle. Give the length of the lifetime of humans, it is easy to understand why so many people assumed it didn’t move at all. And, when it comes to general navigation on Earth, its movement is not really relevant.

So, on Earth, the North Star is our pole star and it has been extremely useful for people living here for millennia. This begs the question, do other planets have pole stars or are we somehow lucky?

The simple answer to this is yes. Given the sheer number of stars in the universe, it is easy to see that if you look out far enough from the pole of any planet, a star would be visible. That being said, however, a pole star is not at all useful unless it is not just visible from the surface of the planet, but easy to distinguish due to its brightness or its association with a constellation.

Even with these stipulations, however, other planets do often have stars that could be considered pole stars.

Mercury, for example, has its north pole pointing almost directly toward a star known as Draco. It would not be as easy to spot in the sky as our North Star, but it could do the trick. On its southern hemisphere, the star Alpha Pictoris will stand out primarily because it is almost perfectly placed at the southern pole of the planet, meaning its motion would be nearly imperceptible, even over the course of hundreds of years.

Mars is the planet that humans are most likely to occupy in the semi-near future, so knowing about pole stars here may be important. The Martian north pole points to the Cygnus constellation, which does not have any extremely bright stars, making it somewhat hard to find. One could use the star Deneb, which is just 9 degrees off of the north pole, but it will be quite bright, being the 19th brightest star in the sky from our solar system. When navigating, however, 9 degrees is a lot so this might not be ideal.

If you move to the south pole of Mars, you will be looking out toward the constellation Vela, which is also known as the “False Cross.” At just 3 degrees off from the south pole, the star Kappa Velorum in that constellation might be a good option, though it still isn’t as bright as our North Star.

No matter what planets we explore in the future, it can be assumed that we will bring the technology needed to be able to successfully navigate without using the stars, but it is always good to have a backup option.

I didn’t realize our North Star was so unique.

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