"Tonight's Sky" is written by retired planetarium director Dave Leake and reprinted with his permission. See Dave Leake's Prairie Skies column in the Champaign–Urbana News-Gazette each Sunday.

March 5–11

Did you see Venus pass Jupiter last week in our southwestern sky? The two planets are still there as we begin March, but they have exchanged places just after sunset. Venus is now the higher of the two. Watch them separate further with each night. Mars still sits in front of the stars of Taurus, over 70 degrees high in the south. By the end of the week the red planet is placed between the two horn stars of the Bull. Look for it above Orion. Tuesday’s full Moon is the “Worm Moon.” As the ground warms, you may start seeing a few earthworms in the grass or on the sidewalk. The Moon, of course, isn’t as squishy.

March 12–18

Daylight saving time begins today – hopefully you set your clocks forward an hour. I was told many years ago that I’d appreciate DST when I had children. Well, my youngest is 29 and I still don’t get it! This Friday the planet Mercury reaches “superior conjunction,” which just means, from our point of view, Mercury passes from the morning sky, behind the Sun, and into the evening sky. So you can’t see Mercury during this time, but I mention it as Mercury will soon begin its best evening view. I’ll be telling you where to look. The rumor is that Copernicus, the dude who suggested the Earth goes around the Sun, never saw Mercury. Don’t be like Copernicus! 

March 19–25

There is a lot going on this week! Tomorrow is the vernal equinox and the first day of spring, beginning at 4:24pm. At this time the Sun appears directly over the Earth’s equator. The Moon is New (and not visible) Tuesday, but emerges from the Sun’s brilliance Wednesday evening to appear really close to Jupiter. But it’s very low in the western sky and a very thin crescent. Start looking at sunset. By Friday, the crescent Moon is above the planet Venus. If the weather permits, the first open house of the year at the Champaign–Urbana Astronomical Society observatory is Saturday, beginning at 7pm and going to 9pm. See for directions and, if the weather is iffy, call 217-351-2567. 

March 26–April 1

Can you still see Jupiter low in the western sky, just after sunset? If so, check it out tomorrow night as Jupiter will have a buddy. Mercury, fresh off its passage behind the Sun, enters the evening sky and sits only a degree and a half to the right of Jupiter. Mercury won’t be quite as bright as Jupiter. As the week progresses, Mercury will gain altitude as it seems to approach Venus. Mercury is much fainter than Venus but there aren’t many bright stars in the area. You’ll get your best view of this elusive planet in mid-April. Tuesday evening, a first quarter Moon appears high in our sky, just left of the planet Mars.