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Brightest Stars

Alphecca: brightest in C-shaped Corona Borealis.
Tonight | Jun 24, 2015

Alphecca, jewel in Northern Crown

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.

Zubeneschamali via nikomi.net
Tonight | Jun 16, 2015

Is Zubeneschamali green?

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

Artist's concept of Kochab seen from its planets via ESky
Tonight | Jun 10, 2015

Kochab and Pherkad

Two noticeable stars in the Little Dipper are said to guard the north celestial pole because they circle so close to Polaris.

Zubenelgenubi via AAO/STScI/WikiSky
Tonight | Jun 04, 2015

Zubenelgenubi is Libra’s alpha star

Zubenelgenubi is an Arabic name that means this star was once seen as the Southern Claw of Scorpius the Scorpion.

Polaris, on left, via Taro Yamamoto
Tonight | May 26, 2015

Polaris is the North Star

The entire northern sky wheels around Polaris. Some assume it’s the brightest star in the sky. In fact, Polaris ranks only 50th in brightness.

Alpha Centauri
Tonight | May 19, 2015

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

Thuban is 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.