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Zubenelgenubi is Libra’s alpha star

It’s now Libra’s alpha star. But Zubenelgenubi is an Arabic name indicating that this star was once perceived as the Southern Claw of Scorpius the Scorpion.

Polaris is the North Star

The entire northern sky wheels around Polaris. But it’s not the brightest star in the sky. In fact, Polaris ranks only 50th in brightness.

Alpha Centauri system, closest to sun

We see this star system as a single star, but it’s really 3 stars. Of the 3, Proxima is closer to our sun than any other known star.

Arcturus cuts through galaxy’s disk

Arcturus, a red giant, looks orange to the eye. It’s the brightest star on the northern half of Earth’s sky dome.

Thuban is a former Pole Star

Thuban was the Pole Star some 5,000 years ago, when the Egyptians were building the pyramids.

Hadar is a southern pointer star

Hadar, aka Beta Centauri, joins Alpha Centauri in pointing to the Southern Cross. It’s a triple system. Two of its stars will someday become nearby supernovae.

Spica is a whirling double star

Spica, the brightest star in the constellation Virgo, is a whirling double star. How to see it in your sky.

Mizar and Alcor, famous double star

Find Mizar and its fainter companion star Alcor in the Big Dipper’s handle.

Cor Caroli, the Heart of Charles

Cor Caroli is a binary star and the brightest star in the northern constellation Canes Venatici, the Hunting Dogs.

Mimosa, 2nd-brightest in Southern Cross

To glimpse Mimosa, you need to be at the latitude of New Orleans, Cairo or New Delhi. From the southern hemisphere, Mimosa is a prominent and beloved star.