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Larry Sessions

Arcturus cuts through galaxy’s disk

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.

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.

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.

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?

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.

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.