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Larry Sessions

Star of the week: Spica

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.

Acrux, brightest star in Southern Cross

You have far south on Earth’s globe to see the Southern Cross. Bluish Acrux, aka Alpha Crucis, is its brightest star.

Regulus: Heart of the Lion

Meet Regulus, brightest star in the constellation Leo the Lion.

Pollux: The brighter Twin star

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 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 near its brighter brother on the sky’s dome.