The white nights have begun: At the North Pole, the sun never sets during the course of the month, in this country it doesn't get really dark until half past ten at the beginning of the month, and at the end of May it doesn't get really dark until midnight. And there is hardly any time to admire the splendour of the stars, because around three or four o'clock in the morning it gets too bright again. Our English-language Sky Guide will tell you what you can observe when and where in May 2020 - you can already find an excerpt here.
When it is finally really dark, the spring pictures are already high in the south. Around midnight the summer triangle peeps over the southeast horizon. Shortly before sunrise you can even catch a glimpse of the autumnal rectangle in the east.
Late in the evening or at dawn: Bright night clouds
In May you can finally discover noctilucent clouds again. This rare celestial spectacle can only be seen on summer nights between May and August - and even then only under special conditions: Extraordinary high clouds are captured by sunlight as darkness sets in. Normally, clouds float at an altitude of about 13 kilometres. To glow, clouds must be in the mesopause of the Earth's atmosphere - and that is at an altitude of more than 80 kilometres! In addition, it must be very cold, around -120 degrees Celsius, because there are ice crystals in the clouds that reflect the sunlight and thus appear to glow. Exchange of places between Venus and Mercury in the evening
Venus, at the beginning of the month still a shining evening star in the western sky, fades more and more in the course of the month. From May 15 on Mercury joins it and can be seen about a hand's breadth to the right below Venus. At first only a few minutes between 21:15 and 21:30, but every evening Mercury stands a little higher and remains visible a little longer. Venus on the other hand is racing towards the sun from our point of view and is not visible at all at the end of May.
Our tip: In the evening of May 22nd, both planets are only half a finger's breadth away from each other: Venus on the right, Mercury on the left. Two evenings later, the young crescent moon joins them. Speaking of the crescent: Venus is then also only recognizable as a narrow crescent - it's best to take binoculars with a tripod.
Planetary trio in the morning
In the southeast sky, early in the morning, before sunrise, Jupiter, Saturn and Mars line up like pearls on a necklace. The most conspicuous, because it is the brightest and largest of the trio of planets, is Jupiter - it can be found on the far right. Right next to him, just over two fingers' breadth away, Saturn accompanies him into the day. Mars is the last one, on the far left. The pretty sight is something for early risers, though - and only until about the middle of the month: Already at half past five it is already too bright again - around five in the morning you should get the best view of all three planets, because at this time Mars has just risen half an hour earlier.
At the end of May, the trio of planets is something for night owls: Jupiter appears in the south-eastern sky shortly after midnight, followed by Saturn around one o'clock, until Mars joins at about three o'clock.
Shooting stars for nights on end
The May aquariums are coming: Between the 3rd and 10th of May, the May aquariums send an average of thirty shots per hour. The highest fall rates are expected during the night of 6 May: then sixty shooting stars per hour are possible! But you can observe shooting stars from the May aquariums the whole month long.
By the way, the May aquariums owe their name to the constellation Aquarius, from which they apparently come. And because Aquarius does not peel over the eastern horizon until two o'clock in the morning, the best time for observation is between four and five o'clock. After that it is too bright. In fact, the May aquariums are dust traces of Halley's comet, which last passed the Earth in 1986.