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Larry Sessions

Star of the week: Acrux

You have to be in the Southern Hemisphere to see the Southern
Cross – in all its glory. Bluish Acrux, aka Alpha Crucis, is its brightest 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. Earthly skywatchers observed it in AD 1054.

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.

What is the crater-dome illusion?

When you see spacecraft images of craters on other worlds, do you sometimes think they look like domes? Here’s how to change your perception.

Castor is 6 stars in one

Castor is one of 2 bright stars in the constellation Gemini the Twins. It appears as a single star, but it’s actually a multiple star system.

Jupiter starts retrograde on February 6

The best time to look for Jupiter is just ahead. Its retrograde motion begins today. A bright star, Spica in the constellation Virgo, is right next to it.

Second-brightest star Canopus

Canopus is the 2nd-brightest star in the sky, and it’s easy to spot on February evenings, if …

See a faint star cluster near bright Sirius

Sirius is easy to find. It’s the sky’s brightest star. If you have binoculars and a dark location, look near it for the star cluster M41.