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Thuban is a former Pole Star

Posted by and in Astronomy Essentials | Brightest Stars | 4 months ago

Thuban was the Pole Star some 5,000 years ago, when the Egyptians were building the pyramids.
Photo of blue-white star Spica.

Spica is a whirling double star

Posted by and in Astronomy Essentials | Brightest Stars | 4 months ago

Spica’s 2 stars orbit a common center of gravity in only 4 days. Their mutual gravity distorts each star into an egg shape, with the pointed ends facing each other.
Observatory dome in foreground, Milky Way in background, and Alpha Centauri's position marked.

Alpha Centauri, star system closest to our sun

Posted by in Astronomy Essentials | Brightest Stars | 5 months ago

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

Alpha and Beta Centauri, pointing to Crux.

Beta Centauri is a Southern Pointer Star

Posted by in Astronomy Essentials | Brightest Stars | 5 months ago

Beta Centauri – aka Hadar – joins Alpha Centauri in pointing to the Southern Cross. Like Alpha, Beta Centauri is also 3 stars, but 2 of Beta’s stars will someday become nearby supernovae.

Cor Caroli, named for the heart of a king

Posted by in Brightest Stars | 6 months ago

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.

Acrux, brightest star in Southern Cross

Posted by in Brightest Stars | 6 months ago

You have to go far south on Earth’s globe to see the Southern Cross. Bluish Acrux, aka Alpha Crucis, is its brightest star.

Alphard is the Snake’s Heart

Posted by in Brightest Stars | 7 months ago

Alphard – Heart of the Snake in constellation Hydra – is ascending in the east in the evening now, a sign of spring coming.

Canopus: Sky’s 2nd-brightest star

Posted by and in Astronomy Essentials | Brightest Stars | 7 months ago

Canopus is the 2nd-brightest star in the sky, and it’s easy to spot on February evenings, if …

Quietly, Regulus ushers in springtime

Posted by in Brightest Stars | 7 months ago

Regulus, brightest star in Leo the Lion, is now rising in the east after sunset. You might not notice it, but stargazers know that, when Regulus appears in this way, spring is near.

Sirius is Dog Star and brightest star

Posted by in Astronomy Essentials | Brightest Stars | 7 months ago

February evenings are a great time to see Sirius. It’s hard to miss the brightest star in Earth’s sky. More about the Dog Star, plus how to spot it