A spring with two stars
In May, Arktur and Spika dominate the first half of the night, leading the way to heaps of deep sky.
In May, after dark, right above our heads, the Big Dipper drives through the zenith. In the photo below you can see this part of the Great Bar constellation marked with lines. In a wide arc, extend the drawbar of the wagon by its approximate overall length. You will end up at Arcturus (Alpha Bootis), the brightest star in the spring sky. Pulling the bow further brings you to Spika (AlphaVirginis), the brightest star of an otherwise inconspicuous but large constellation: Virgo ("Virgo"). Arcturus is the second brightest star in our Central European night sky after Sirius in the Great Dog and ahead of Capella in the Fuhrmann. It stands at 0.0 magnitude in the firmament and shows a slight yellow-orange tint. Its name means "bear keeper". We usually also call the constellation that houses it the same sun - although its Greek name Bootes actually means "ox driver". Star and constellation follow the Great Dipper incessantly on his orbit across the northern sky.
Spika is significantly less brilliant than Arcturus at 1st magnitude. In the constellation Virgo, she represents an ear of wheat in the hands of a maid who sows the spring grain. Northwest of Virgo, not far from the star Denebola, the tip of Leo's tail, is one of the favorite regions of trained observers. With the naked eye or small binoculars you can only see a few faint stars there. Only with larger binoculars or a telescope can you spot a multitude of fuzzy flares scattered throughout the Virgo galaxy cluster. Each of these clouds is a galaxy similar to our Milky Way - but at a distance of fifty to sixty million light years.
For observers with binoculars, the hair of the Berenices ("Coma Berenices") offers a worthwhile target. Just below the westernmost star, you can already make out a faint glimmer with the naked eye: the Coma star cluster, Melotte 111. It fills the entire field of view with binoculars
Planets in May
Mercury will pass behind the Sun on the night of the 19th. It can be seen at dusk from the following week until the end of June.
Jupiter shines low in the southeast at dusk, rising to an altitude of around 25 degrees after midnight. The inconspicuous constellation Libra ("Libra") is currently home to it. Its brightest star is the binary Alpha Librae at 2.7 mag. The two suns have no chance against the giant planet, which shines with minus 2.5. Magnitude a hundred times as bright, for it is in opposition on May 4th and closest to Earth two days later. Its disc therefore grows to an impressive 45 arc seconds. Even with a medium-sized telescope, you can distinguish the planet's many darker belts from the brighter ones and see the famous Great Red Spot, which is actually more brown.
Saturn and Mars are moving towards each other in the western evening sky. The ringed planet is clearly the brighter one. Venus is the only visible planet in the morning sky. Bright and lonely she stands at dawn in the East.
The Moon will still be young when it will be near Mars on the evenings of May 1st and 2nd. A slightly thicker crescent moon is on the 3rd between Saturn and Pollux. On the evening of May 10th it is one and a half degrees west of Spika, on the 11th and
12. On the morning of May 24, the thin crescent Moon hovers three degrees above rising Venus. Back in the evening sky on the 27th you have a chance to see an extremely thin crescent. In the graphic above, the moon has just disappeared to the northwest behind the wind turbines. On May 30th the moon forms a beautiful ensemble with Mars and Pollux, at night with Mars and Saturn. © astronomy today
