Enjoying EarthSky? Subscribe.

248,143 subscribers and counting ...

Use Big Dipper to locate Hunting Dogs

If you can find the Big Dipper, you can also find 2 Hunting Dogs – aka Canes Venatici – seen by the ancient stargazers to be nipping at the Bear’s heels.

Star of the week: Acrux

You have far south on Earth’s globe to see the Southern Cross. Bluish Acrux, aka Alpha Crucis, is its brightest star.

Know the Big and Little Dippers

The Big Dipper is easy. And, once you find it, you can find the Little Dipper, too. Plus … learn how the stars of the Big Dipper are moving in space.

A mysterious star called Epsilon Aurigae

Epsilon Aurigae’s light dims for a period of about 2 years, in a 27-year cycle. The star’s last dimming was from 2009 to 2011.

A tangle of stars in Berenices’ Hair

Coma Berenices – aka Berenices’ Hair – requires a dark sky to be seen. But it’s worth the effort, a wonderful star cluster!

Where’s the moon? Waning crescent

A waning crescent moon is sometimes called an old moon. It’s seen in the east before dawn. Next new moon is March 28 at 02:57 UTC.

Is Sirius the most luminous star?

To astronomers, the word “luminous” refers to a star’s intrinsic brightness. Sirius is our sky’s brightest star, but only because it’s relatively nearby at 8.6 light-years away.

Arcturus, a northern springtime star

Orange Arcturus is the constellation Bootes the Herdsman’s brightest star. Look for it in the east around nightfall.

Equinox sun rises due east, sets due west

How can the sun rise due east and set due west – for all of us – on the day of the March equinox? Explanation, charts, diagrams, here.

Equal day and night on equinox?

The sun is a disk, not a point of light. Plus Earth’s atmosphere refracts sunlight. For both reasons, we have more than 12 hours of daylight on the day of an equinox.

Fastest sunsets near equinoxes

We’re talking about the amount of time needed for the body of the sun to sink below the horizon. It’s true. The sun actually sets faster around the time of an equinox.

Venus about to leave evening sky

And Mercury is climbing into it. By late March, Venus will have moved to the east before dawn as Mercury stages its best evening apparition of the year for northern observers.

Regulus: Heart of the Lion

Meet Regulus, brightest star in the constellation Leo the Lion.

Westward shift of Orion and all the stars

The famous constellation Orion disappears into the sun’s glare every year at this time. It happens as Earth makes its grand tour each year, around the sun.

Where’s the moon? Waning gibbous

Watch for the moon late at night now, or before dawn. Last quarter moon will come on March 20, the same date as the equinox.

Use Big Dipper to find Little Dipper

The Big Dipper is easy to recognize, but the Little Dipper … not so much. Here’s a tip that can help.

Use Big Dipper to find North Star

Here’s how to spot Polaris, aka the North Star. The 2 outer stars in the Big Dipper’s bowl point to it.

Moon and Jupiter March 13 and 14

Jupiter and the moon will appear as nighttime’s two brightest lights. They’ll be close as seen from around the world.

Full-looking moon edges toward Jupiter

On March 12, 2017, look east as darkness falls to see a brilliant, full-looking moon. Bright Jupiter will rise shortly after the moon, by early to mid-evening.

What’s special about a full moon?

Why does a full moon tug our heartstrings? And why does the moon on this night look full, in contrast to other other nights and other phases of the moon?