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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.

Photo by John Ashley.  See more of his work on Facebook.

Vision quest

Seven shield-bearing warriors stand guard below the rising Milky Way, in a very special place in Montana.

Hot Jupiters, exoplanets around the same size as Jupiter that orbit very closely to their stars, often have cloud or haze layers in their atmospheres. This may prevent space telescopes from detecting atmospheric water that lies beneath the clouds, according to a study in the Astrophysical Journal. Image via NASA/JPL-Caltech

Exoplanets’ water hidden by clouds?

Hot Jupiters have masses like our Jupiter, but orbit their stars closely. They often have cloud or haze layers, which, a new study says, may hide atmospheric water.


Astral dream

A light painting under the stars of southern Maine.

Sky wheeling around Polaris, the North Star.

Does the North Star ever move?

It’s a symbol for constancy, but, if you took its picture, you’d find that the North Star makes its own little circle around the sky’s north pole every day.

Image via ESA/NASA

Night shining clouds from ISS

A view of noctilucent – or night shining – clouds from the International Space Station.