by Deane Morrison
The familiar winter stars head into the sunset during April, dropping westward as Earth leaves them behind in its movement around the sun. In the midst of them is Mars, the nearest of the outer planets. Being so close to the sun, Mars orbits at a higher speed than any planet further out"”so fast that it's hard for Earth to shake Mars off in the orbital race. This month, the Red Planet postpones its fate by moving several degrees eastward against the background of stars, rushing past them like a salmon swimming upstream. Watch Mars escape through the horns of Taurus into Gemini, en route to Cancer and Leo before finally disappearing this summer.
Mars' eastward motion this month carries it closer to Saturn, which still hugs the Beehive star cluster of Cancer. On the 25th, viewers with telescopes will get a great 3-D view of the planet and its rings. Saturn will then be 90 degrees east of the sun, throwing its shadow as far as possible eastward onto the rings.
Moving eastward again, we encounter Jupiter in Libra. Outshining every planet save Venus, Jupiter rises earlier each evening in April. Going before the king of planets in its nightly journey is Spica, the brightest star in Virgo. Jupiter will be at its best early in May, when Earth shoots between the planet and the sun.
Venus, somewhat low but still brilliant, lights up the predawn sky. Mercury barely makes it into the sky to the lower left of Venus during the first week in April. But on the 18th, viewers with binoculars or a telescope may find a more exotic companion. Uranus will appear as a tiny bluish green dot near Venus, just a little more than half a full moon width to its lower right.
The moon opens the month as a waxing crescent right next to the Pleiades star cluster. On the 13th comes the full moon, known to Algonquin Indian tribes as the grass moon, the egg moon or the pink moon (for the flowers of the wild ground phlox). The moment of fullness is at 11:41 a.m., well after moonset, so take your choice whether to look at it that night or the night before. Easter Sunday (the 16th) ends with a waning moon rising just before midnight very close to the bright red star Antares, in Scorpius.
In April the kingly figure of Leo rides highest in the southern sky. The lion displays his heart as the bright star Regulus, Latin for "prince."¯ Regulus anchors the Sickle, a group of stars in the form of a backward question mark. Leo's entourage is impressive: Leading him is the Beehive cluster, and bringing up the rear is another cluster called Coma Berenices. Both dazzle the eye when seen through binoculars.
The Lyrid meteor shower peaks sometime after 10:30 p.m. the night of the 21st. Although predicting the number of meteors per hour is difficult, Lyrids are typically fast and can be quite bright, with persistent trails. The meteors radiate from a spot just west of the brilliant star Vega in Lyra, which clears the eastern horizon by around 10 p.m.
The month goes out with a bang, at least for fans of Celtic history. The night of the 30th ushers in the Celtic holiday Beltane, one of the cross-quarter days falling midway between an equinox and a solstice. The night, immortalized by Goethe in his epic poem Faust, was a witches' sabbath when evil spirits had a last fling before being banished until Halloween. Goethe and modern-day celebrants in the Harz Mountains of Germany know the occasion as Walpurgis Night, while we call it May Day.
Daylight time returns officially at 2 a.m. on the 2nd. Clocks should be set one hour ahead.