Future North Star

Future North Star

Future North Star

The only thing we knew was that we loved everything North Star. So we packed a few bags, drove across the country and started a new life in their kitchen.


Precessional wobbling causes this NCP displacement. The influence of the Sun, Moon and, to a lesser extent, planets, cause Earth's pole to precess over a long time period. One can observe a similar behavior in spinning gyroscopes. As the gyroscope rotates, the top repeatedly describes a circle due to precessional wobbling. Our planet's wobble is much longer, of course, so that even over a human lifetime, its effects are subtle. Because of precession, different stars will serve as north stars and the constellations arrayed along the ecliptic (zodiac) will gradually change positions. Their move about one degree every 73 years.

Polaris will remain the North Star throughout the rest of our lives and for a few centuries later. Throughout the past few centuries, Polaris has served as a North Star marker for navigators, escaping slaves and other explorers. During this time, the NCP has appeared to be drawing closer to Polaris and continues to do so, today. By 2102, the NCP and Polaris will attain their minimum separation distance of 27'. After 2102, the NCP will slowly move away from Polaris and within 2,000 years will pass close to Errai, a star within Cepheus the King. Although Errai is about three times dimmer than Polaris and the NCP won't ever be as close to it as it was to Polaris, observers in 2,000 years will likely use Errai as the North Star. (Source: usm.maine.edu)


The circular path of the north celestial pole (in orange), due to axial precession, relative to the stars. Over the course of about 26,000 years, the Earth’s rotational axis, projected onto the sky, will trace a circle in northern and southern skies. Positive numbers in yellow show dates in CE (Common Era) where the north celestial pole will be located relative to the stars. Negative numbers in yellow represent BCE (Before Common Era) dates. Polaris is shown near the top of the circle at 2,000 CE, our current time. Image via Tau’olunga/ Wikimedia Commons.

While other stars might line up with the north celestial pole during the 26,000 year cycle, they do not necessarily meet the naked eye limit needed to serve as a useful indicator of north to an Earth-based observer, resulting in periods of time during the cycle when there is no clearly defined North Star. There will also be periods during the cycle when bright stars give only an approximate guide to "north", as they may be greater than 5° of angular diameter removed from direct alignment with the north celestial pole. (Source: en.wikipedia.org)



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