May Starwatch

In May the nighttime darkness gets squeezed into just a few hours by the expanding light of summer. But no matter; mosquitoes are still few, and stars are many. Most of the action takes place in the evening, now that Venus has dropped from the morning sky on its latest trip behind the sun.

In the west, Mars, moving rapidly against the backdrop of stars, staves off the inevitable descent into the sunset as it drops behind Earth in the orbital race. Its glory faded, the Red Planet forsakes Gemini and makes a beeline for Leo. But watch it between the 22nd and 24th, when it crosses the Beehive star cluster west of the lion's head. Through binoculars it'll make one of the rarest and most beautiful sights of the year.

Mars is heading for an encounter with the bright star Regulus, the heart of Leo, and Saturn, now just a few degrees east of Regulus. Saturn doesn't wait for Mars, however. On the 3rd the ringed planet begins a long trek eastward, away from Regulus, and won't be back to visit for 30 years.

Saturn, too, is being left behind by speedy Earth, and its rings are closing; therefore, if you have a telescope, now is the time to view it. On the 22nd it will be 90 degrees east of the sun, a highly favorable position for sunlight and shadows to highlight the rings' 3-D structure.

Jupiter, in Sagittarius, begins rising before midnight in mid-month. The massive king of planets will reach its greatest brightness in about two months, when Earth passes between it and the sun.

The moon appears as a thin crescent just above the sunset glow on the 6th. If you can find it, you may be able to spot Mercury just below and a little to the left. It should be highest and most visible around the 13th, after which it falls back toward the sun.

The flower moon rises near the claws of Scorpius shortly after sunset on the 19th, barely a quarter-hour before reaching fullness. Thus, we'll be treated to the sight of a perfectly round, softly glowing orb rising over the eastern horizon. Also known to Algonquin Indians as the corn planting moon or milk moon, it will trace a low arc over the night sky and set just before sunup.

Looking to the south, you'll see bright Spica, in Virgo. Spica forms a westward-pointing triangle with Arcturus, the brilliant anchor of kite-shaped Bootes, to the north and Regulus in the west. Framing the entire evening sky is the Milky Way, which hugs the horizon tightly nearly all the way around.

The Eta Aquarid meteor shower, though not as famous as the Perseids or Leonids, could be one of the better ones this year. Its peak occurs on the 5th, but at 1 p.m. CDT, so we'll miss it. Still, Eta Aquarids will be sprinkled over much of the month. There's just one catch: We'll have to get up early because the meteors radiate from a spot in the Water Jar of Aquarius, which doesn't rise until an hour or two before dawn.