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after midday, and Mars will have shifted a bit, westward, on the sky's dome. So Mars is high in the southwest now at sunset.
• Can you see Mars? Absolutely! It's not as bright as it was in early March 2012, when Mars was at opposition or opposite Earth from the sun (see diagram below). But Mars is still bright.
• In fact, it's one of the first "stars" to pop into view when the sun goes down. Ruddy Mars is still the brightest "star" in the constellation Leo the Lion, shining a little bit more brightly than Regulus, Leo's alpha star and the star that represents the

Lion's Heart.
• Incidentally, the moon reaches eastern quadrature every month at first quarter moon. At first quarter phase, we see half of the moon's daylight side and half of its nighttime side. Since Mars will be at eastern quadrature, can we expect Mars to look like the first quarter moon through a telescope? The answer is no.
• Unlike the moon, Mars shows us its thinnest phase when at quadrature - but, as an outer planet, Mars' thinnest phase isn't very thin. Mars will still look roly-poly through a telescope. It'll look like the waxing gibbous moon - more than half lighted but less than full. Presently, the red planet exhibits about 89% of its daylight side and 11% of its nighttime side.
• After reaching eastern quadrature tonight, Mars will remain in the evening sky for the rest of this year. It'll stay fairly bright and prominent throughout the northern summer of 2012. However, Mars will fade by northern autumn, as this world begins its long slide toward the glare of the setting sun.
• Bottom line: Mars reaches a milestone on June 7, 2012: eastern quadrature at 9 p.m. Central Daylight Time. It's half a sky's dome away from the sun now, still bright, still in front of Leo - getting farther away from Regulus, Leo's brightest star.
• What is the ecliptic?