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Larry Sessions

Star of the week: Alpha Centauri

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

Star of the week: Arcturus

Arcturus, a red giant, looks orange to the eye. It’s the brightest star on the northern half of Earth’s sky dome.

Hadar is a southern pointer star

Hadar, aka Beta Centauri, joins Alpha Centauri in pointing to the Southern Cross. It’s a triple system. Two of its stars will someday become nearby supernovae.

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.

Spica is a whirling double star

Spica, the brightest star in the constellation Virgo, is a whirling double star. How to see it in your sky.

The Coma Cluster of galaxies

The Coma Cluster is one of the richest galaxy clusters known. How many suns and how many worlds might be located in this direction of space?

10 surprises about our solar system

Here are 10 unexpected and intriguing facts about our solar system – our sun and its family of planets – you probably did not know!

Moon near Gemini stars on April 3

Gemini’s 2 brightest stars – Castor and Pollux – represent twins in many cultures.

Mimosa, 2nd-brightest in Southern Cross

To glimpse Mimosa, you need to be at the latitude of New Orleans, Cairo or New Delhi. From the southern hemisphere, Mimosa is a prominent and beloved star.

Crab Nebula

Look for the Crab Nebula

The Crab Nebula, about 6,500 light years from Earth, is the scattered fragments of a supernova, or exploding star, observed by earthly skywatchers in the year 1054.