Astronomy events for April 2012

SkyCaramba weekly astronomy blog for the week ending March 31, 2012 

April begins with Venus above Jupiter in the west. Venus and Jupiter are both climbing upward against the starry background. But they are becoming visible a little later each evening because of later sunsets. 

Venus is heading toward the Pleiades and passes them on the 3rd and 4th. The planet will be just 34’ from Merope on the 3rd at 00:34 UT. That’s just slightly more than a full moon’s width away. Venus is even closer to Alcyone, at 24’ separation at 15:53 on the same date. And it’s closer still to Alcyone on the 4th at 00:28 with just 14’ separation. 

A very thin crescent moon passes Jupiter on the 21st. The best places to see it from are those at about 18° north latitude. Puerto Rico, the Hawaiian Islands, and central India are among the places well situated. The moon’s a little thicker but still a crescent shape when it passes by Venus on the 24th

Orion, long thought of as a winter constellation in the northern hemisphere, is setting shortly after the sun these evenings. Seeing Orion going down and not having to be out in a heavy coat may remind you of the winter that was not long ago. Gemini sets a little after Orion. 

Leo’s on the meridian by mid-evening. Spot red Mars just below it. A nearly full moon passes it on the 3rd. The red planet is inching westward each night toward Regulus. But Mars hesitates around the 11th. By the 24th, it should be clear that Mars is moving eastward again. The moon, a little newer than in the earlier encounter, passes Mars again on the 30th

Virgo rises in mid-evening. Saturn is near the constellation’s bright star Spica. The ringed planet is moving westward as if aiming for a point north of Spica. The moon passes 2° from Spica on the 6th. Saturn is at opposition on the 15th. It’ll be up all night. Saturn’s 8.7 astronomical units (Earth-Sun distances) away for this opposition. It was slightly closer, 8.6 AU, last year. Next April, Saturn will be at opposition again, a little farther, at 8.8 AU. This year’s opposition will be the ringed planet’s third in a row in Virgo. Next year, it will still be close to Virgo, but barely inside the Libra constellation lines. 

The April Lyrid meteor shower peaks on the 22nd with no moon in the sky to wash out the view this year. You may see 10 to 20 meteors an hour at its peak. These meteors tend to leave trails that linger for several seconds. The April Lyrid shower is hard to predict, so it’s not easy to tell you what to expect. But that’s what makes astronomers excited about it. They don’t know if there might be an unusually high peak as happened in 1982 and a rate of 90 per hour were seen. 

I hope you have clear skies at the right times. ¡SkyCaramba!