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Star of the week: Castor

Castor is one of 2 bright stars in the constellation Gemini the Twins. It appears as a single star, but it’s actually a multiple star system.

Sirius is Dog Star and brightest star

Sirius – the Dog Star – is the sky’s brightest star. It’s very easy to spot on winter and spring evenings.

Second-brightest star Canopus

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

Elnath is close to the galactic anticenter

Elnath, the 2nd-brightest star in Taurus, is the closest bright star to the galactic anticenter – the point in space directly opposite of our Milky Way’s center.

Capella is 2 golden stars

We see Capella as the brightest star in the constellation Auriga the Charioteer. It’s actually 2 stars, each with a golden color similar to our sun.

Rigel in Orion is blue-white

Blue-white Rigel, in the constellation Orion, is one of the brightest stars in the night sky. It’s about twice as hot, and 40,000 times brighter, than our sun.

Aldebaran is the Bull’s fiery eye

Aldebaran – brightest star in the constellation Taurus the Bull – is huge! If it were in our sun’s place, its surface would extend almost to the orbit of Mercury.

Betelgeuse will explode someday

Someday, the star Betelgeuse will run out of fuel, collapse under its own weight, and then rebound in a spectacular supernova explosion. Someday … but probably not soon.

Mirfak is Perseus’ brightest star

Mirfak isn’t as famous as its brother star in Perseus, called Algol. But Mirfak is easier to find and can help guide you to Algol.

Menkar is the Whale’s alpha star

It’s not the most famous star in Cetus, or the brightest, although it carries the designation Alpha. But Menkar has its own claims to fame.

Hamal is an ancient equinox star

Hamal, also known as Alpha Arietis, is the brightest star in Aries the Ram. Learn the role this star played in defining the term First Point in Aries.

Mira the Wonderful

This star in the constellation Cetus varies in brightness over about 11 months. Its next brightness maximum is due in early 2017.

Almach is a quadruple star system

Almach looks like a single star to the eye and like a colorful double star through a telescope. But today we know Almach as four stars.

Achernar is the End of the River

Achernar – also known as Alpha Eridani – is the 9th brightest star in Earth’s sky and the flattest star known.

Al Risha knots Fishes of Pisces

The star Al Risha in Pisces is not bright. But – at the tip of the graceful V in Pisces – it’s very noticeable.

Algol is the Demon Star

What’s the scariest star in all the heavens? Around Halloween, look for Algol – a star named for a demon!

Deneb Kaitos is the Sea-Monster’s Tail

Look for Deneb Kaitos – brightest star in Cetus the Whale – highest in the sky around mid-evening.

Schedar lies at the Queen’s heart

Cassiopeia the Queen is an easy-to-find constellation from northerly latitudes. It has the shape of an M or W. Schedar is the Queen’s brightest star.

Alpheratz is part of the Great Square

Come to know this star and be one step further along the path of finding the Andromeda galaxy.

Gamma Cephei: A future Pole Star

Gamma Cephei (aka Errai) is a binary star system with at least one planet. It’ll someday be a Pole Star for Earth.