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Moon inside Winter Circle on February 27


The waxing gibbous moon on February 27 resides in or near a large asterism that we in the Northern Hemisphere often call the Winter Circle. It’s an incredibly large star configuration made of brilliant winter stars. From North America on this night, the moon is inside the Circle. If you’re in the Southern Hemisphere … although it’s not winter for you, these same stars appear near the moon.

Moon skims north of Orion on February 26


The waxing gibbous moon will be shining to the north of the constellation Orion the Hunter as darkness falls on February 26, 2015. Yet the moon will be south of the ecliptic – the annual pathway of the sun in front of the backdrop stars.

Bright star near moon on February 25 is Aldebaran

Tonight – February 25, 2015 – if you live at far-northern latitudes, you might see the moon hide the star Aldebaran, brightest light in the constellation Taurus, for a portion of the night. In Iceland, Greenland, and northern Europe, the moon will occult – cover over – Aldebaran for up to an hour or so. Not at a far-northern latitude? That’s okay! You’ll have an awesome view of this bright star near tonight’s moon.

Waxing moon in Taurus, heading toward Jupiter


Tonight – February 24, 2015 – the fat waxing crescent moon shines in front of the constellation Taurus the Bull. Despite the lunar glare, you should be able to make out the Bull’s brightest star, Aldebaran, and the tiny, dipper-shaped Pleiades star cluster, aka the Seven Sisters.

Star of the week: Procyon the Little Dog Star

Orion with his Dogs. The Dog Stars are Sirius in the constellation Canis Major, and Procyon in the constellation Canis Minor. In this photo, Orion is in the upper right. Notice that the three stars of Orion’s Belt point to the brightest star in this photo, Sirius. Procyon is the bright star on the far left of the photo. Procyon and Sirius make a large triangle with the bright star Betelgeuse in Orion. Photo by Daniel McVey in Colorado. Thank you, Daniel!

It’s hard to think of Procyon – the Little Dog Star – without also thinking of the other Dog Star, Sirius. If you’re looking at the right time of year (or right time of night), you can always find Sirius because it’s the sky’s brightest star. Procyon is always near its brighter brother on the sky’s dome. Procyon isn’t nearly as bright as Sirius. It’s the 8th brightest star in the sky, and the 6th brightest of stars that are easily visible from the most populated regions of the Northern Hemisphere. Follow the links inside to learn more about Procyon, the Little Dog Star.

Beehive: 1,000 stars in Cancer

Van Macatee in Rutledge, Georgia caught asteroid 2004 BL86 as it swept near the Beehive star cluster on the morning of January 27, 2015.

We saw some beautiful shots of the Beehive cluster in early 2015, when the close-passing asteroid 2004 BL 86 swept near it in the sky. Van Macatee in Rutledge, Georgia captured this photo on the morning of January 27, 2015.

Although it is one of the 12 constellations of the Zodiac, Cancer the Crab is so faint that you’d likely never notice it … except for the lovely star cluster in its midst. This cluster is commonly known as the Beehive, or M44. It’s a wonderful swarm of stars, glimpsed with the eye in a dark location and easily found in binoculars. Its size is 1.5 degrees, or three full moon diameters. Although the eye cannot detect them, it contains a thousand stars.

Watch for Mercury before dawn this week


Mercury, the innermost planet of the solar system, never strays far from the sun in Earth’s sky. For that reason, this world is often lost or obscured by the sun’s glare. But on February 24, 2015, Mercury reaches its greatest angular distance west of the sun (26.75o), so this world can now be seen in the eastern sky before sunrise. Astronomers call this a greatest elongation of Mercury.

Stars and planets in the daytime


People often ask if stars are up there, beyond our blue sky, during the day. The answer is surely yes, because Earth is a planet in space, surrounded on all sides by stars. The constellation behind the sun around now is Aquarius the Water Bearer. Every year, the sun passes in front of Aquarius from about February 16 to March 12.

Venus and Mars in conjunction below moon on February 21


Tonight – February 21, 2015 – is the closest conjunction of the planets Venus and Mars since September 11, 2008. They won’t couple up this closely again until October 5, 2017. As soon as darkness falls, look for these embracing worlds to pop out beneath the waxing crescent moon in your western sky. If you have binoculars, aim them at dazzling Venus to see nearby Mars with Venus in a single binocular field of view!

Glorious moon and planets at nightfall February 20


Think photo opportunity! The waxing crescent moon and the planet Venus – the brightest and second-brightest orbs of nighttime, respectively – will be the first two celestial bodies to pop out after sundown. Look westward, starting around 30 to 45 minutes after sunset. Then as dusk ebbs into darkness, watch for the planet Mars to join the brilliant twosome. If you have binoculars, aim them at Venus to spot Mars all the sooner in the darkening sky.