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Orion the Hunter and Sirius the Dog Star

You’ll always know it’s the sky’s brightest star, Sirius, if the very noticeable constellation Orion the Hunter is nearby.


Great Square of Pegasus points to Andromeda galaxy

We showed you how to use Cassiopeia to find this galaxy. Now try star-hopping from the Great Square of Pegasus.

Phobos, via Viking 1.  Image Credit:  NASA

Today in science: A moon for Mars

American astronomer Asaph Hall discovered Phobos, one of the two Martian moons, on this date in 1877. Did he imagine how well we’d see Mars’ moons today?

Geminid meteor, Lovund, Nordland, Norway.
 Photo via Tommy Eliassen.

How high up do meteors start glowing?

Meteors begin to glow almost as soon as they hit Earth’s atmosphere, but tend to vaporize (burn up completely) at varying altitudes.

Randy Baumhover captured this image at Meyers Creek Beach on the Oregon coast.

Top 10 tips for meteor-watchers

How to watch a meteor shower. Tips for beginners.

You'll find Scutum above the constellation Sagittarius, in the south on N. Hemisphere summer evenings.

Scutum the Shield named for Polish king

The constellation Scutum has just 4 noticeable stars, and even those require a dark sky.

After sunset. Photo: Loire Vignolle-Moritz

What exactly is twilight?

Twilight is the time of day between daylight and darkness. Astronomers, the experts on nighttime, recognize three kinds of twilight.

Photo credit: Mike Quinn

How can I see a green flash?

It’s said that once you’ve seen a green flash, you’ll never go wrong in matters of the heart. Here’s all you need to know … plus great pics.


Astronomy festivals, star parties, workshops

Looking for something to do on the weekends? At star parties, amateur astronomers with telescopes will show you the night sky. Find one near you …

Fallen trees at Tunguska.  This image is from 1927, when Russian scientists were finally able to get to the scene.  Photograph from the Soviet Academy of Science 1927 expedition led by Leonid Kulik.

Today in science: The Tunguska explosion

On June 30, 1908, an explosion over Siberia killed reindeer and flattened trees. But no crater was ever found. It may have been a small asteroid.