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Moon near star Antares on August 23


Antares in the constellation Scorpius is the bright red star near the moon tonight. In ancient Chinese thought, the summer season was associated with the direction south, element fire, and color red. This red star in the south each summer – Antares – was considered the Fire Star of the ancient Chinese.

Moon closest to Saturn on August 22


No matter where you live worldwide, look for the moon as evening falls on August 22. It’ll appear half-illuminated, shining near the star Antares and the planet Saturn.

Moon, Saturn, Antares on August 21-23

The moon moves eastward relative to the background stars and planets of the Zodiac. The dark side of the waxing moon  points eastward - in the moon's direction of of travel. The green line depicts the ecliptic - Earth's orbital plane projected onto the constellations of the Zodiac.

The moon moves eastward relative to the background stars and planets of the Zodiac. The dark side of the waxing moon points eastward – in the moon’s direction of of travel.

Tonight – August 21, 2015 – watch for the rather wide waxing crescent moon, the planet Saturn and the star Antares to adorn the sky as darkness falls. For us at northerly latitudes, they’ll be in the southwest. From mid-latitudes in the S. Hemisphere, you’ll see them in the northwest. Take a stroll with a loved one, or family and friends, to see all these celestial luminaries lighting up starry heavens first thing at nightfall.

Moon moving toward Saturn on August 20


If you saw the moon last night, you probably noticed the star Spica nearby. Spica is still fairly close to the moon tonight, but you can see that the moon has moved in relationship to this star. That motion of the moon is due to the moon’s actual motion in orbit around Earth. In a few more days, the moon will partner up with the planet Saturn.

Born between November 29 and December 18? Here’s your constellation

Ophiuchus the Serpent Bearer via Wikimedia Commons.

Ophiuchus the Serpent Bearer via Wikimedia Commons.

Astrological signs versus astronomical constellations, how to locate Ophiuchus, some deep-sky treasures it contains, plus charts and more.

Deneb is distant and very luminous

The star Deneb is one of the largest stars known. It is one of the most distant stars you will see with your eye alone.

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. The exact distance to Deneb is unclear, with estimates ranging from about 1,425 light-years to perhaps as much as 7,000 light-years. Whatever its exact distance, when you gaze at Deneb, know that you are gazing across thousands of light-years of space.

Moon near star Spica on August 19


As soon as darkness falls on August 19, look low in the southwest sky for the waxing crescent moon and the star Spica. Over the next few days, at nightfall, watch for the moon to move away from Spica and toward the planet Saturn. Be sure to catch the moon and Spica as soon as darkness falls, for the two will follow the sun beneath the horizon shortly thereafter.

Summer Triangle on August evenings

Here is the Summer Triangle asterism – three bright stars in three different constellations – as photographed by EarthSky Facebook friend Susan Jensen in Odessa, Washington.

We’ve recently seen Orion’s return to the east before dawn, which means our northern summer is beginning to draw to the a close. But the Summer Triangle asterism still rules the skies. You can see it overhead this evening.

Cassiopeia points to Andromeda galaxy

In a dark sky, you might spot the Andromeda galaxy with no optical aid, as the ancient stargazers did before the days of light pollution. But what if you can’t find the Andromeda galaxy with the eye alone? Some stargazers use binoculars and star-hop to the Andromeda galaxy via this W-shaped constellation. Cassiopeia appears in the northeast sky at nightfall and swings high to the north as evening progresses. Note that one half of the W is more deeply notched than the other half. This deeper V is your “arrow” in the sky, pointing to the Andromeda galaxy.

Great Square of Pegasus points to Andromeda galaxy


The Andromeda galaxy – also known as M31 – is faint but can be seen by the unaided eye or binoculars in a very dark sky. The galaxy is a huge island of stars in space, thought to look similar to our own Milky Way galaxy. Tonight’s sky chart shows you how to star-hop to this galaxy from the Great Square of Pegasus.