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Jupiter and Earth’s moon, and the beautiful dance of Jupiter’s moons


If you’ve been watching these past few days, you know the waxing gibbous moon has been moving past the glorious planet Jupiter in our night sky. The feature sky chart at top shows the moon’s position relative to Jupiter and the star Regulus as seen on the evening of March 3 from North America. In the world’s Eastern Hemisphere – Africa, Europe and Asia – the moon still shines between Jupiter and Regulus on March 3, but is more offset toward Jupiter.

Moon closest to Jupiter on March 2


Tonight – March 2, 2015 – look for the brilliant waxing gibbous moon to pair up with the dazzling planet Jupiter as soon as darkness falls. As the Earth spins eastward beneath the starry heavens tonight, it’ll cause the moon and Jupiter to travel upward and westward, until the brilliant twosome reaches its high point in the sky at late evening. They’ll continue to move westward, to set in the west just before dawn.

Moon nears Jupiter on March 1

At the same time each evening, note the moon's change of position relative to the backdrop stars. The green line depicts the ecliptic -  pathway of the moon and planets.

At the same time each evening, note the moon’s change of position relative to the backdrop stars. The green line depicts the ecliptic – pathway of the moon and planets.

The bright waxing gibbous moon passes through a “stellar pathway” in late February/early March 2015, and will do so again toward the end of March 2015. Each month, as the moon journeys through the constellations of the Zodiac, it always swings to the south of the Gemini stars Castor and Pollux, and to the north of the star Procyon, the brightest in the constellation of Canis Minor the Lesser Dog.

What is the Zodiac?

March 2015 guide to the five visible planets

Skywatcher, by Predrag Agatonovic.

Skywatcher, by Predrag Agatonovic.

Three of the five visible planets are in good view in March 2015. Venus and Jupiter shine first thing at nightfall. Jupiter will be near the moon in early March, closest around March 2. Meanwhile, Saturn adorns the late night and predawn sky.

Moon between Gemini stars and Procyon on February 28


Tonight’s bright waxing gibbous moon will be bright enough to erase many stars from the blackboard of night. Even so, three stars should be brilliant enough to withstand tonight’s moonlit glare – the Gemini stars, Castor and Pollux, plus Procyon the Little Dog Star. In late February and early March, the moon passes south of the Castor and Pollux, and north of Procyon, the brightest star in the constellation Canis Minor the Lesser Dog.

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.