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Orion’s Belt and the Celestial Bridge

To the Aymara of Bolivia, Orion’s Belt is the Celestial Bridge, uniting the sky’s northern and southern hemispheres.

The moon, Venus and Mars as seen from North America on December 4, 2016. But no matter where you reside worldwide, look first for the moon on this date, and then seek out Venus and Mars. Read more

Moon and Mars closest December 4

Use the moon to find Mars this evening. Bright Venus is nearby. Then watch day by day, as the gap on our sky’s dome between Mars and Venus shrinks.


Don’t miss moon and Venus December 2

The moon and Venus are the 2 brightest nighttime objects. Think photo opportunity! Or just enjoy these 2 beauties in the west early Friday evening.

These are star trails, and one of the brightest trails here is Alpha Arietis, or Hamal.  To learn which one, click here, then click on the image you find.  This neat image is by Herb Raab on Flickr.

Star of the week: Hamal

Hamal, also known as Alpha Arietis, is the brightest star in Aries the Ram. Learn the role this star played in defining the term First Point in Aries.


Aries? Here’s your constellation

How and when to see the constellation Aries in the night sky, plus info about this constellation in the history of astronomy and in mythology.

Skywatcher, by Predrag Agatonovic.

December guide to the bright planets

Three bright planets appear at nightfall in December 2016: Mercury, Venus and Mars. Jupiter reigns as the sole morning planet. Saturn is lost in the sun’s glare.


Moon and Mercury on November 30

In North America, on November 30, the moon sets after Mercury. South of the equator – in South America – Mercury sets after the moon.

A new moon is more or less between the Earth and sun.  Its lighted half is turned entirely away from us. Image via memrise.com.

New moon is November 29

A new moon rises and sets with the sun and crosses the sky during the day. You won’t see it today, but the moon will return to the evening sky and appear near bright planets, in the days ahead.


Sun enters Ophiuchus on November 29

The sun always passes in front of Ophiuchus from about November 29 to December 18. That’s why some call Ophiuchus an unofficial member of the Zodiac.

View larger. | Photo by Jeff Dai

Can we see stars outside our Milky Way?

When we look up or down – away from the flat disk of the galaxy or toward it – we’re seeing Milky Way stars. But we also see a few more distant objects, visible to the eye alone.

5% illuminated waning crescent moon rising in New Delhi, India by Chander Devgun.

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 November 29 at 12:18 UTC.


Use Pegasus to find Andromeda galaxy

The wonderful Andromeda galaxy! Most distant object we can see with the eye alone. Try using the Great Square of Pegasus to find it in a dark sky.

Mira, from NASA's Galaxy Evolution Explorer

Mira the Wonderful

This star in the constellation Cetus varies in brightness over about 11 months. Its next brightness maximum is due in early 2017.

The constellation Cassiopeia points to the Andromeda galaxy.  To see the galaxy, you need a dark sky.

Use Cassiopeia to find Andromeda galaxy

One half of the W of Cassiopeia is more deeply notched than the other half. This deeper V is your “arrow” in the sky, pointing to the Andromeda galaxy.


Summer Triangle in northern autumn

The Summer Triangle is made up of the three brilliant stars Vega, Deneb and Altair. Look for it this evening in your western sky.

Triangulum galaxy - aka M33 - via the VLT Survey Telescope at European Southern Observatory's Paranal Observatory in Chile.

Messier 33 is the 2nd-closest spiral galaxy

Triangulum galaxy, aka Messier 33. is 2.7 million light-years away, and the third-largest member of our Local Group, after the Milky Way and Andromeda galaxies.

Watch for the moon to be in Jupiter's vicinity for several mornings, centered on November 26. Read more

See moon and Jupiter before sunup

The moon has been taking aim on Jupiter for several mornings. On November 25, they’re closest for the Americas … beautiful as seen from around the world.


Mercury and Saturn, moon and Jupiter

Mercury and Saturn are in conjunction on November 23, but hard to spot in the sunset glow. On the mornings of November 24 and 25, the moon appears near Jupiter before dawn.


A famous variable star in Cepheus

With clock-like precision, the star Delta Cephei doubles in brightness every 5.36 days. You can notice this brightness change with the eye alone.

The moon was almost exactly at last quarter when Jenney Disimon in Sabah, North Borneo captured this photo on July 27, 2016 (5:30 a.m. local time, or July 26 at 21:30 UTC).

Last quarter moon on November 21

Fun time to see a last quarter moon: just after it rises, shortly after midnight. Then the lighted portion points downward, to the sun below your feet.