Enjoying EarthSky? Subscribe.

129,823 subscribers and counting ...

Tonight

Use brightest star Sirius to imagine sun’s path through Milky Way

Not sure which star is Sirius? The three Belt stars of Orion – three stars in a short, straight row – always point to Sirius.

You can use the brilliant star Sirius to imagine the direction our sun and solar system are traveling through space. The sun in its orbit is traveling away from Sirus and toward the star Vega (which shines over the northwest horizon – opposite Sirius – at this time of year). So if you stand outside in the evening with your back to Sirius – facing northwest – you’ll be facing the direction our solar system moves through the Milky Way galaxy.

Moon and stars of Aries point to Phantom galaxy on January 25

2015-jan-25-aries-moon-night-sky-chart

Use the moon on the nights of January 25 and 26, 2015, to find three stars outlining the head of the constellation Aries the Ram (Hamal, Sheratan and Mesartim). Then, when the moon moves out of the evening sky in the second week of February 2015, use these three stars to find an elusive galaxy – Messier 74 – also known as the Phantom galaxy.

Moon and Uranus in front of Pisces on January 24 and 25

2015-jan-24-uranus-moon-night-sky-chart

The waxing crescent moon and planet Uranus, the seventh planet outward from the sun, float in front of the constellation Pisces the Fishes on the evenings of January 24 and 25, 2015. Although Uranus will remain within Pisces’ borders for the rest of this year, the moon will leave Pisces after a few more days. With the moon waxing to full now, you’re not likely to glimpse Uranus with the unaided eye. But click inside, anyway. We give you an idea of its location, and links to detailed charts, in this post.

Mars between moon and Venus on January 23

2015-jan-23-venus-mars-moon-night-sky-chart

The above sky scene is for North American mid-northern latitudes. Farther east on the globe – Europe, Africa, Asia, Australia and New Zealand – the waxing crescent moon is found closer to the red planet Mars. Look westward as soon as darkness falls, because Venus will follow the sun beneath the horizon at early evening.

Moon, Mars, Venus as darkness falls January 22

2015-jan-22-venus-mars-moon-night-sky-chart

Tonight, go outside soon after sunset on January 22, 2015, and look west! On this night, you can use the waxing crescent moon to find the planets Mars and Venus. Then keeping watching over the coming month. Venus will gain ground on Mars on our sky’s dome. The two will planets will finally rendezvous on February 21, 2015. That late February conjunction of Venus and Mars will be their closest on our sky’s dome until October 5, 2017.

Young moon and Venus after sunset January 21

2015-jan-21-venus-mercury-mars-moon-night-sky-chart

The above sky chart shows the young moon and evening planets as they appear at North American mid-northern latitudes on January 21. The planets will be similarly positioned at mid-northern latitudes in Europe and Asia, except that a thinner waxing crescent moon will lurk even closer to the horizon (and the planet Mercury). At mid-northern latitudes, you might need binoculars to spot Mercury some 60 to 70 minutes after sunset. Although everyone worldwide should be able to view dazzling Venus about 45 to 60 minutes after sundown, given clear skies and an unobstructed western horizon, it’ll be harder to catch the young moon and Mercury from southerly latitudes in the Southern Hemisphere.

Star of the week: 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

new-moon-young-moon

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

19jan10_430

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.