Mars is less than one month away from its March 3, 2012 opposition when it will be best for this two-year period. Let the moon show you Mars tonight!

On the night of February 9, 2012, the moon, Mars and the constellation Leo the Lion are seen together over the eastern horizon about two to three hours after sunset. Regulus, Leo’s brightest star, rises first at nightfall or early evening. Then the moon and Mars follow Regulus into the sky some 60 to 90 minutes later. The moon might look full to you, but it’s really now in a waning gibbous phase. Does Mars look reddish to you in the moon’s glare?

The fainter stars of Leo might be hard to make out in the lunar glare tonight, but Regulus, Leo’s brightest star and one of the brightest stars in our night sky, will be easy to spot. Mars beams even more brilliantly than Regulus, and is found near Denebola, the star that depicts “the Lion’s Tail.”

Regulus: Lion Heart

Venus and Uranus remain within one binocular field for the next several evenings, though Venus climbs upward, away from Uranus.

But wait. Back up – and now think western sky, not eastern sky. Before the moon rises tonight, on February 9, 2012, look westward as darkness falls for the dazzling planet Venus, the brightest starlike object in the starry sky. If you have binoculars or a low-powered telescope, aim them at Venus to catch the faint planet Uranus nearby. From mid-northern latitudes in North America, Uranus will appear to the immediate left of Venus, or as seen from Asian mid-northern latitudes, Uranus will be to Venus’ upper left. Venus and Uranus will occupy the same binocular field of view for the next several evenings, though Venus will climb a little higher above Uranus with each passing day.

At roughly the time that Venus and Uranus set – or around three hours after sunset – the Regulus/moon/Mars trio begin their ascent in the east.

February 2012 guide to the five visible planets

Mars is a planet and moves in front of the star background, making a beeline around the entire sky – through all the constellations of the Zodiac – once every two years. Leo’s stars, like all stars, are much more steadfast. They rise four minutes earlier each day, or two hours earlier with each passing month. Sometime in March 2012, watch for Leo to light up the eastern sky as soon as darkness falls – a sure sign that spring is about to return to the Northern Hemisphere.

Like the sun, the stars of Leo the Lion swing full circle across the sky once a day. This movement is due to Earth’s spin under the sky.

Unlike the sun, however, the stars return to the same place in the sky in 23 hours and 56 minutes – not 24 hours. This is happening because – as Earth spins – it’s also moving through space, in orbit around the sun. And as we move, our night sky points out a constantly changing panorama of the Milky Way galaxy.

The 4-minute difference between the return of the stars (sidereal day) and the sun (solar day) may seem insignificant, but this discrepancy adds up over time. Because of it, we associate certain stars with certain seasons of the year. If the stars returned to the same place in the sky every 24 hours, we wouldn’t have seasonal constellations.

In short, all the stars rise about 4 minutes earlier with each passing day. One and one half months from now – around the March 20 equinox – the stars of Leo the Lion will rise some 3 hours earlier than they do tonight.

How do we know about our galaxy’s shape?

Bottom line: Look for the moon, Mars and stars of Leo the Lion in the east about two to three hours after nightfall. Then watch for these Leo stars and Mars to appear above the eastern horizon as soon as darkness falls sometime in March. Mars is now nearly at its best for this two-year period. Its opposition – when Earth flies between Mars and the sun – will come on March 3, 2012.