Enjoying EarthSky? Subscribe.

116,386 subscribers and counting ...

Anticrepuscular rays in a Texas sky

Photo credit: Kenneth G. Smith

Photo credit: Kenneth G. Smith

Next time you see crepuscular rays extending from a sunset … turn around. Look opposite the the sun. You might catch a glimpse of elusive anticrepuscular rays, as Kenneth G. Smith in the east Texas did in this photo. More about anticrepuscular rays, inside.

Use Big Dipper to find Polaris, the North Star


You can find the North Star, Polaris, using the two outermost stars in the bowl of the Big Dipper. On September evenings, look for the Big Dipper in the northwestern sky. Notice that a line from the two outermost stars in the bowl of the Big Dipper point to the North Star. The Big Dipper circles the North Star much like an hour hand circling the center of a clock.

Favorite photos of September 12 aurora

Star trails and the September 12 aurora, as captured by Mike Lewinski in Maine.

Star trails and the September 12 aurora, as captured by Mike Lewinski in Maine.

Two powerful storms on the sun this week released solar particles that began striking Earth’s atmosphere early Friday morning (September 12, 2014). As a result, many at northerly latitudes – and some at latitudes like those of the northern U.S. – saw beautiful displays of the northern lights last night. These are a few of our favorites. Thanks to all who posted on EarthSky’s Facebook page.

Moon and Pleiades late night September 13 until dawn


You can find the Pleiades star cluster – sometimes called the Seven Sisters – easily just by looking for it. No other pattern in the sky is so little and yet so clearly shaped like a dipper. Late at night on September 13, 2014, until dawn on September 14, you can see the waning gibbous moon near this star cluster. The bright reddish star nearby is called Aldebaran.

New scans reveal hidden monuments of Stonehenge

Image credit: University of Birmingham

Image credit: University of Birmingham

The startling results of a new survey include 17 previously unknown monuments and dozens of burial mounds surrounding Stonehenge.

First evidence for water-ice clouds outside our solar system

This artist's conception shows the object named WISE J085510.83-071442.5. Imabe courtesy of NASA/JPL-Caltech/Penn State University

Artist’s concept of brown dwarf W0855, one of the closest brown dwarfs to our sun at only 7 light-years away. Recent evidence suggests water-ice clouds in the atmosphere of W0855. Image courtesy of NASA/JPL-Caltech/Penn State University

Significant auroras predicted for tonight

View larger. | Colin Chatfield near Saskatoon, SK, Canada captured this aurora Friday morning.  Taken with a Canon 7D and Tokina 10-17mm fisheye lens at 10mm, f/3.5, 20 sec exp, ISO 800.  Visit Colin Chatfield on Facebook.

View larger. | Colin Chatfield near Saskatoon, SK, Canada captured this aurora Friday morning.

Due to two recent events on the sun – including an X-flare from Active Region 2158 on the sun on Wednesday – reports from NOAA and elsewhere predict good chances for significant auroral displays. Auroras will be possibly observable at latitudes as far south as the northern U.S. states including, for example, Wisconsin, Michigan, and New York, and maybe even farther south. Spaceweather.com reports:

The first of two CMEs expected to hit Earth’s magnetic field on Sept. 12 has arrived, and a minor (G1-class) geomagnetic storm is underway as a result of the impact. The second and potentially more powerful CME is still en route. NOAA forecasters say geomagnetic storming could become strong (G3-class) during the late hours of Sept. 12 and Sept 13 after the second CME arrives.

Look for Cassiopeia the Queen in northeast after sunset now


Cassiopeia the Queen can be found in the northeast after sunset on September evenings. This constellation has the distinct shape of a W, or M, depending on the time of night you see it. The shape of this constellation makes Cassiopeia’s stars very noticeable.

Video: Jellyfish flame on the ISS

Fire in space doesn’t act like fire here on Earth. Untethered by gravity, flames in space curl themselves into tiny balls. Here’s a new NASA video on experiments on combustion in microgravity aboard the International Space Station.

Rosetta spacecraft selfie with comet

Via ESA/Rosetta/Philae/CIVA.

Rosetta spacecraft ‘selfie’ with comet 67P/Churyumov–Gerasimenko, imaged Sunday, September 7, 2014. Image via ESA/Rosetta/Philae/CIVA.

Here is a Rosetta ‘selfie’ with comet 67P/Churyumov–Gerasimenko in background. It was taken by the CIVA camera onboard the Philae Lander. This is the same camera that will be acquiring images from the surface of the comet itself, when the Philae lander sets down on the comet in November.