Alpheratz belongs to Andromeda, but is part of the Great Square

Alpheratz appears to our eyes as a single star but it is actually a close binary star system. Many stargazers use it to locate the Andromeda galaxy.

Delta Cephei helps measure cosmic distances

Delta Cephei is an inconspicuous variable star in the northern constellation Cepheus the King. This important star helped establish the cosmic distance scale.

Meet Delta Scorpii, aka Dschubba, it’s a variable star

Delta Scorpii, also known as Dschubba, is a variable star in the constellation Scorpius. With the eyes alone, you can check its brightness for yourself.

Zubenelgenubi is the alpha star of Libra the Scales

Zubenelgenubi - Alpha Librae - is a double star, and is the second brightest star in the constellation Libra the Scales.

Tonight’s young moon emerges into the evening sky

The young moon will compete in brightness with several bright stars on the evening of May 9, 2024. Which will shine most brightly?

Cor Caroli, named for the heart of a king

Cor Caroli is a binary star and the brightest star in the northern constellation Canes Venatici, the Hunting Dogs. Its name means Heart of Charles.

Beta Centauri is one of the Southern Pointer Stars

Beta Centauri isn’t as famous as Alpha Centauri, but together, these brilliant Southern Hemisphere stars have inspired legends and guided mariners.

Bright Procyon: The Little Dog Star in Canis Minor

The Dog Star, Sirius, is easy to spot because it's the sky's brightest star. Procyon - the other Dog Star - is near its brighter brother on the sky's dome.

Menkar – a visual double – is the Whale’s alpha star

It's not the most famous star in Cetus the Whale, or the brightest. But Menkar is the Whale's alpha star and has its own claims to fame.

Mirfak is the brightest star in Perseus the Hero

Mirfak is the brightest star in Perseus and is visible even from light-polluted locations. This star is a member of the Alpha Persei Moving Cluster of stars.

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