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Brightest Stars

Alpha Centauri
Tonight | May 19, 2015

Star of the week: Alpha Centauri closest star system to our sun

Third star in the system, a red dwarf called Proxima Centauri, is our sun’s closest neighbor at about 4.22 light-years.

Arcturus.
Tonight | May 13, 2015

Arcturus cuts through galaxy’s disk

Arcturus is cutting perpendicularly through the galactic disk at a tremendous rate of speed – some 150 kilometers per second.

Great Pyramid of Giza
Tonight | May 05, 2015

Star of the week: Thuban, a former Pole Star

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

Artist's concept of Spica from hypothetical planet
Tonight | Apr 22, 2015

Spica is a whirling double star

Spica is a binary star, with two stars larger and hotter than the sun, telescopically indistinguishable from a single point of light.

Image Credit: ESO Online Digitized Sky Survey
Tonight | Apr 15, 2015

Mizar and Alcor, a famous double star

Mizar and its fainter companion star Alcor are located in the handle of the Big Dipper. They are one of the sky’s easiest-to-spot double stars.

Cor Caroli by F. Ringwald, Fresno State
Tonight | Apr 09, 2015

Cor Caroli or Heart of Charles

The star Cor Caroli, or Alpha Canum Venaticorum, is a binary star and the brightest star in the northern constellation Canes Venatici.

Constellation Crux photo by Christopher J Picking in New Zealand.  More information about this photo here.  Used with permission
Tonight | Apr 01, 2015

Mimosa is second-brightest in Southern Cross

If you’re in the U.S., you must be at about New Orleans’ latitude to glimpse it. From the southern hemisphere, Mimosa is a prominent and beloved star.

Constellation Crux photo by Christopher J Picking in New Zealand.  More information about this photo here.  Used with permission
Tonight | Mar 24, 2015

Acrux, brightest star in Southern Cross

You have to be in the Southern Hemisphere to see Crux – the Southern
Cross – in all its glory. Bluish Acrux, aka Alpha Crucis, is its brightest star.

Credit: Russell Croman
Tonight | Mar 18, 2015

Regulus is the Lion’s Heart

Meet Regulus, brightest star in Leo the Lion.

Alphard.  (North Central Kansas Astronomical Society)
Tonight | Mar 09, 2015

Alphard is the Snake’s Heart

You can see Alphard – the Heart of the constellation Hydra the Water Snake – in the evening in March, April, and May.

Golden Pollux
Tonight | Mar 04, 2015

Pollux the brighter Twin star

Being so close together in the sky, Pollux and its brother star Castor are easy to compare. Pollux is brighter and golden in color, while Castor is fainter and white.

Procyon
Tonight | Feb 23, 2015

Procyon is the Little Dog Star

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

Castor system via Jeremy Perez
Tonight | Feb 16, 2015

Castor six stars in one

Two stars noticeable for being bright and close together might be Castor and Pollux of the Gemini Twins constellation.

Canopus seen from ISS
Tonight | Feb 06, 2015

Will you see Canopus?

Canopus is sky’s second-brightest star and easy to spot on February evenings, if …

Betelgeuse imaged in ultraviolet light by the Hubble Space Telescope and subsequently enhanced by NASA. The bright white spot is likely one of this star's poles. Image via NASA/ESA.
Tonight | Jan 29, 2015

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.

Elnath represents the Bull's Northern Horn.
Tonight | Jan 20, 2015

Elnath is close to the galactic anticenter

Elnath is the second-brightest star in Taurus the Bull. It’s the closest bright star to the galactic anticenter – the point in space that lies directly opposite of the center of our Milky Way galaxy.

Capella system, via Atlas of the Universe
Tonight | Jan 13, 2015

Capella is two golden stars

We see Capella as the brightest star in the constellation Auriga the Charioteer. It is really two stars, each with a golden color similar to our sun.

Blue-white Rigel via Clark Planetarium
Tonight | Jan 06, 2015

Rigel in Orion is blue-white

We couldn’t live as close to Rigel as we live to our sun, because Rigel is nearly twice as hot – and about 40,000 times brighter – than our local star.

Aldebaran-Sun_comparison_cropped
Tonight | Dec 29, 2014

Aldebaran is the Bull’s fiery eye

If Aldebaran were placed where the sun is now, its surface would extend almost to the orbit of Mercury.

Mirfak and Algol in Perseus
Tonight | Dec 22, 2014

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.

Look south in late autumn / early winter
Tonight | Dec 08, 2014

Menkar is the Whale’s alpha star

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