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Larry Sessions

Achernar is the End of the River

Achernar – aka Alpha Eridani – is the 9th brightest star in the sky and the flattest star known.

Small Magellanic Cloud orbits Milky Way

You need to be in Earth’s Southern Hemisphere to see the Small Magellanic Cloud. It looks like a luminous cloud, but it’s really a dwarf galaxy, orbiting our Milky Way.

Shedding light on the moon’s dark side

A far side of the moon remains hidden from Earth, but doesn’t stay permanently dark.

Alpheratz is part of the Great Square

Finding the star Alpheratz can help you spot the Andromeda Galaxy, the nearest large spiral galaxy to Earth.

5 myths about the moon

Moon myths, take that! Here are 5 of the most common myths about our moon explained.

Use Big Dipper to find North Star

The 2 outermost stars in the bowl of the Big Dipper point to Polaris, the North Star.

Fomalhaut had first visible exoplanet

How to see the star Fomalhaut in your sky and a word about Fomalhaut b, the first planet beyond our solar system visible to the eye in photographic images.

Deneb is distant and very luminous

Deneb is one of the most distant stars you will see with your eye alone. That’s because it’s one of the most luminous stars in the Milky Way galaxy.

Altair is the bright star of the Eagle

Altair needs only 10 hours to spin once on its axis, in contrast to roughly a month for our sun. This mighty star spins on its axis faster than Earth does!

Earth’s eclipses are special

Solar eclipses aren’t exclusive to Earth, but eclipses viewed from our planet have few rivals in the solar system. A word about Earth’s solar eclipses, and what eclipses would be like on other planets, here.