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Posts by
Larry Sessions
Summer Triangle star: Altair spins fast!
Altair is only 16.8 light-years from Earth, making it one of our closest stellar neighbors. It's variable in an usual way, and it spins fast!
July 8, 2021
Summer Triangle star: Deneb is distant and luminous
When you gaze at the bright star Deneb, Tail of the Swan, you’re gazing across thousands of light-years of space at one of the bright stars of the huge Summer Triangle asterism.
July 7, 2021
Summer Triangle star: Vega is bright and blue-white
There's a noticeable star pattern called the Summer Triangle in the east on July and August evenings. Its brightest star is blue-white Vega.
July 2, 2021
Ruby red Antares is the Scorpion’s Heart
Red Antares, Heart of the Scorpion in the constellation Scorpius, is a mighty star, a red supergiant.
June 22, 2021
Arcturus, brightest star of the north
Arcturus is the 4th brightest star in the sky and the brightest star north of the celestial equator. One of the easiest stars to locate due to its position off the handle of the Big Dipper, you can look for it on spring evenings in the Northern Hemisphere.
May 14, 2021
Moon and Gemini stars on April 18 and 19
Watch for Gemini's 2 brightest stars - Castor and Pollux - near tonight's moon. On the other side of the moon, you'll see a 3rd bright star. It's Procyon in the constellation Canis Minor, the Lesser Dog.
April 18, 2021
Beta Centauri is a Southern Pointer Star
Beta Centauri isn’t as famous as Alpha Centauri, but together, these brilliant Southern Hemisphere stars have inspired legends and guided mariners.
April 9, 2021
Leo loses his tail. We gain a constellation
The constellation Leo once had a tail, a clump of faint stars. Now these same stars are known as Coma Berenices, the hair of a queen.
April 9, 2021
Alpha Centauri, star system closest to our sun
Our closest stellar neighbors are the 3 stars that make up the Alpha Centauri system. They lie just over 4 light-years - about 25 trillion miles or 38 trillion km - away.
April 7, 2021
The Coma Cluster contains thousands of galaxies
Myriads of galaxies, visible only to those with medium-to-large telescopes, shine among the stars in the "Realm of the Galaxies." Study of the Coma Cluster of galaxies aided in the discovery of dark matter.
April 7, 2021
