Unlock the Secrets of Ursa Minor: Your Ultimate Guide to Finding the ‘Other Dipper’ This Summer with the North Star

This week, let’s explore Ursa Minor, or the Little Bear. Many new stargazers mistakenly think the Pleiades star cluster is the Little Dipper. But in reality, the Little Dipper’s stars are not very bright, making it hard to spot in light-polluted areas.

The Little Dipper’s seven main stars form a shape resembling a dipper. At the end of its handle lies Polaris, known as the North Star. If you’re in a city with bright lights, spotting Polaris can be a challenge. The best way to find it is by using the “Pointer” stars, Dubhe and Merak, from the Big Dipper. Just draw a line between them and extend it about five times; you’ll be in the vicinity of Polaris.

Your view of Polaris changes based on where you are. For example, from Minneapolis, it sits halfway between the horizon and the zenith, the highest point in the sky. If you’re at the North Pole, Polaris is directly overhead. Conversely, at the equator, it appears right at the horizon. As you move north, Polaris climbs higher in the sky. However, if you head south, it dips below the horizon and disappears once you cross into the Southern Hemisphere.

The two stars at the front of the Little Dipper’s bowl are often called the “Guardians of the Pole.” They spin around Polaris, marking the location of the North Star. Historical figures like Columbus noted these stars during their sea voyages, using them to navigate the night sky.

Among the Guardians, Kochab shines the brightest with an orange hue, while Pherkad is dimmer and has an interesting name from Arabian lore meaning “the Dim One of the Two Calves.” Their brightness levels help amateur astronomers gauge sky clarity. If you can see all four stars in the bowl, you’re looking at a good sky. Unfortunately, many in urban settings might only see the Guardians due to light pollution.

An interesting fact: the Big and Little Dippers are positioned so that when one is upright, the other is upside down. This creates a striking contrast where the Big Dipper stands out as a bright pan while the Little Dipper looks just like a dim ladle.

Polaris is fascinating beyond being just a North Star; it’s a triple star system. The main star is a massive yellow supergiant located 446 light-years away. Despite its fame, Polaris isn’t the brightest star in the sky, ranking 47th. It’s a Cepheid variable star, meaning its brightness changes slightly over days, making it a unique and intriguing celestial object.

Interestingly, due to the Earth’s axial precession, Polaris will continue to move closer to the celestial pole. By March 24, 2100, it will be at its closest point to the pole. Historically, stars like Kochab served as the North Star around 1200 B.C. during the Iron Age.

In recent years, light pollution has diminished our view of the night sky. A survey by the International Dark-Sky Association reported that one-third of the world’s population can’t see the Milky Way due to light pollution. So next time you gaze at the stars, remember the stories and history hidden in the constellations above.

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