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Elnath is close to the galactic anticenter

On August evenings, we look toward the center of our Milky Way galaxy. On January and February evenings, we look toward the galaxy's nearest our edge - toward the anticenter of the Milky Way. The star Elnath lies just three degrees from the galaxy's anticenter.

You know how, in August, we look toward the center of our Milky Way galaxy? In January and February, we do the opposite. In the evening, we look opposite the galaxy’s center, toward the galactic anticenter and the galaxy’s nearest outer edge. The star Elnath (sometimes also called Alnath) in the constellation Taurus the Bull is the closest bright star on our sky’s dome to the galactic anticenter. Follow the links inside to learn more about the star Elnath, and about looking toward the anticenter of the Milky Way.

In 2015, first of six supermoons comes on January 20


We will have six supermoons in 2015, and the first of the bunch is to fall on January 20, 2015.

What, you say? Supermoon? But the moon isn’t anywhere near full on this date! That’s right. This isn’t a full supermoon. Rather, it’s a new supermoon. In fact, the new moons on January 20, February 18 and March 20 all qualify as supermoons. Follow the links in this post to learn more about the supermoons of 2015.

Understanding new moon

New moon: night side of moon facing Earth

The new moon falls tomorrow – January 20 – at 13:14 Universal Time. On the day of new moon, the moon rises when the sun rises. It sets when the sun sets. It crosses the sky with the sun during the day.

The image above is imaginary. It’s as if you flew in a spaceship to a place where you could see the night side of the moon. Why do we say imaginary? Because, when the moon is new, its night face is facing us on Earth … and we can’t see the moon at this time.

See Monoceros the Unicorn on dark January nights


You’ll need a very dark sky to see the constellation Monoceros the Unicorn in the sky on these cold winter nights. The constellation Monoceros represents a Unicorn on the night sky dome. It is faint and all but impossible to see in any but the darkest skies. If you draw a line between the bright stars Sirius and Procyon, you will find yourself in the territory of the Unicorn. Try sweeping with binoculars for the star cluster M50.

Star-hop from Great Square of Pegasus to Andromeda galaxy


This evening, try star-hopping to the famous Andromeda galaxy – the large spiral galaxy next-door to our Milky Way – from the Great Square of Pegasus. Ready? Here’s how to do it.

Cassiopeia and Big Dipper on opposite sides of North Star

The northern sky’s two most prominent sky patterns – the constellation Cassiopeia the Queen and the Big Dipper – both circle around Polaris, the North Star, once a day. They are opposite each other, one on either side of the North Star. On January evenings, Cassiopeia shines high in the north while the Big Dipper lurks low. Look again before dawn to see the Big Dipper up high and Cassiopeia down low.

Moon near Antares and Saturn, plus Orion and the Scorpion

Let the waning crescent moon be your guide to the planet Saturn and the star Antares before sunrise on Saturday, January 17.

Let the waning crescent moon be your guide to the planet Saturn and the star Antares before sunrise on Saturday, January 17.

Before dawn on Saturday – January 17, 2015 – watch for the waning crescent moon near the star Antares, brightest star in the constellation Scorpius the Scorpion. Not a morning person? Then look for the constellation Orion the Hunter, which dominates the sky in early evening. In the lore of the sky, Orion is tied intimately to Scorpius, which – at this time of year – can be found rising shortly before dawn.

Moon and Saturn before dawn on January 16


For several days, the waning crescent moon shines close to the planet Saturn and the Crown of the Scorpion in the predawn sky, centered on Friday, January 16.

Mercury farthest from setting sun on January 14


Tonight – or any night this week – look for Mercury, our solar system’s innermost planet. As dusk gives way to darkness on these mid-January 2015 evenings, the dazzling planet Venus can help guide you. Mercury reaches its greatest eastern elongation (greatest distance from the sun on the sky’s dome) on January 14. With Mercury near Venus – the sky’s third-brightest object after the sun and moon – Mercury is unusually easy to find after sunset now.

Capella is two golden stars

Capella is really two golden stars. Image via Atlas of the Universe

Capella is the brightest star we see at night of the same spectral type, or color, as our daytime star, the sun. Like our sun, Capella appears as a yellow or golden star. It is the brightest yellow star visible in our sky – much bigger and brighter than our sun in absolute terms, but of course much farther away, about 42 light-years in contrast to the sun’s 8 light-minutes. Follow the links inside to learn more about Capella.