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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.

Venus and Jupiter will be exceedingly close together Saturday evening!  Don't miss them low in the west, shortly after sunset.

Venus-Jupiter conjunction August 27

Spectacular Venus-Jupiter conjunction! They’re the two brightest planets, and it’s the closest conjunction of two planets in all of 2016. Don’t miss it!

61 Cygni is a double star, captured here by Scott MacNeill at Frosty Drew Observatory, Charlestown, Rhode Island, June 2015.

Star of the week: 61 Cygni

61 Cygni isn’t bright. But it moves exceptionally rapidly against the background of more distant stars. Its motion reveals its nearness to Earth.


Every visible star is within Milky Way

On August evenings, in a dark country sky, you’ll easily spot the starlit band of our huge, flat Milky Way galaxy.


Constellation Cepheus looks like a house

The constellation Cepheus represents a King, but looks like the stick house that children draw.


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.

Hoax image via social media.

No double moon in 2016, or ever

We thought we might get through this summer without the dumb hoax about Mars as big as a full moon rearing its head. But, no.

Mars moves in between the planet Saturn and the star Antares on August 24, 2016.Read more

2016’s great Mars and Saturn conjunction

Mars, Saturn and the star Antares have made a triangle in our sky for months. Now see them in a straight(ish) line.

Waning gibbous moon on the morning of July 24, 2016, by Ruy Queiroz in São Paulo, Brazil.

Where’s the moon? Waning gibbous

Look for the waning gibbous moon to rise in the middle of the night. It might look strangely oblong.


Cassiopeia points to Andromeda galaxy

Easiest way to find the large spiral galaxy next door. Try it, next time you’re under a dark sky.


How to watch a solar eclipse safely

Tips on eclipse-watching. Order your eclipse glasses now!

As autumn 2013 begins, there is a daytime moon in the morning sky.  Our friend Michelle Shoenberger Fritz captured it over Strasburg, Pennsylvania.

See the daytime moon

The daytime moon floats pale and beautiful against a blue sky. Look west after sunrise!


Quasi-conjunction of Mercury and Jupiter

Venus and Jupiter are super bright, near the sunset glare. Mercury is nearby.


Deneb is distant and very luminous

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.


Born under the sign of Ophiuchus?

Born between November 29 and December 18? If so, the sun passes in front of Ophiuchus on your birthday.


What’s special about a full moon?

You know it when you see it, but what makes a full moon full?

Image credit: Bruce Fingerwood

Moon past full. How to see Neptune

Tonight’s moon looks full but is already waning. This moon is near Neptune on the sky’s dome. How to find Neptune when the moon moves away.

Image credit: Katie Steiger-Meister/USFWS

Sturgeon, Green Corn Moon August 17-18

We in North America also call the August full moon the Corn Moon or Grain Moon. For us in the Americas, it comes before dawn Thursday.


Mercury greatest elongation August 16

Mercury is in the west after sunset, and it’s farthest from the sun tonight for this evening apparition. How to spot it.

Earth's shadow is the blue-grey band closest to the horizon.  The Belt of Venus is the pink band above the shadow.

See Earth’s shadow and Belt of Venus

Earth’s shadow is a deep blue-grey, darker than the twilight sky. The pink band above the shadow – in the east after sunset, or west before dawn – is called the Belt of Venus.