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Delta Cephei doubles in brightness every 5.36 days and thereby helped establish the known distance scale of our galaxy and universe.

While not one of the most conspicuous stars in the night sky, Alderamin – aka Alpha Cephei – is easy to spot, and is interesting for its rapid rotation on its axis.

Altair needs only 10 hours to spin once on its axis, in contrast to roughly a month for our sun. This mighty star spins on its axis faster than Earth does!

Albireo is known best for the striking color contrast between its two stars – the brighter gold star and the dimmer blue star.

Binoculars reveal that Epsilon Lyrae is a double star – two stars in one. A telescope shows that each component star is also a double. The double double star!

One of the prettiest stories in all skylore surrounds this star. “On the 7th night of the 7th moon … “

Alphecca. Gemma. Alpha Coronae Borealis or simply Alpha Cor Bor. They’re all names for one star – the brightest star in the constellation Northern Crown.

Kochab and Pherkad – 2 stars in the Little Dipper – are called Guardians of the Pole. How to find them and more.

Although some scientists claim stars can’t look green, many stargazers will swear that Zubeneschamali proves otherwise.

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.

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.

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

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

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.