Sky Calendar 2027: What to Mark and What to Sleep Through

How to read the calendar

With showers you will see the abbreviation ZHR, the zenithal hourly rate. It is the calculated number of meteors per hour that an ideal observer would see under a perfectly clear sky with the shower’s radiant directly overhead. You will see fewer. Sometimes far fewer.

The second thing is the Moon. Its light drowns out faint meteors just as a street lamp does. So for every shower we give the Moon’s phase too. And the third: at opposition a planet sits opposite the Sun in the sky, rises as the Sun sets, is visible all night and is at its brightest.

Winter: January to March

The year opens with its best. The Quadrantids are active from 28 December to 12 January and peak on 4 January at 4:25 a.m. CET, with a ZHR of about 80. New moon falls on 7 January, so the Moon stays out of the way. The IMO rates the conditions as perfect. The peak is brief, which makes the night of 3–4 January the one to pick. Warm socks count as equipment.

In February two planets reach opposition: Jupiter on 11 February and Mars on 19 February. You will find them close together in the sky, and on 31 March only about four degrees will separate them.

On the night of 20–21 February there is a penumbral lunar eclipse, from 10:12 p.m. to 2:13 a.m. CET, with its maximum at 12:12 a.m. All of it is visible from here. Honestly, though: the Moon passes only through the Earth’s penumbra and darkens very slightly. Anyone who does not know something is happening will notice nothing.

Spring: April to June

Spring 2027 is quieter. The Lyrids are active from 14 to 30 April, peaking on 23 April at 3:40 a.m. CEST with a ZHR of about 18. But full moon is on 21 April, and the bright Moon shines just as the radiant climbs. According to the IMO, the Lyrids have the worst conditions of the whole year. Sleep soundly.

The summer solstice falls on 21 June at 4:11 p.m. CEST. Around it the nights here never get properly dark, as you know from the main story.

Summer: July to September

Monday 2 August belongs to the Sun. The path of totality crosses southern Spain, North Africa and the Arabian Peninsula. In Egypt totality will last up to 6 minutes 23 seconds. From here you will see a partial eclipse. In Prague it begins at 10:14 a.m., peaks at 11:14 and ends at 12:17 p.m. CEST. In Bratislava it peaks at 11:18 and in Košice at 11:23. The Moon will cover roughly half the Sun’s diameter.

One rule with no exceptions: never look at the Sun without protection. You need eclipse glasses or a handheld solar viewer that meets the ISO 12312-2 standard. Sunglasses will not do, however dark. Look through a camera, binoculars or a telescope only with a solar filter fitted over the front of the instrument.

The Perseids are active from 17 July to 24 August. The maximum, with a ZHR above 110, falls on 13 August between 10 a.m. and noon CEST: daytime here. The best night is 12–13 August, with the radiant reasonably high from ten or eleven in the evening. The catch: the Moon is between first quarter and full, so the moon-free time will be quite short, says the IMO. Look for it before dawn.

The penumbral lunar eclipses of 18 July and 17 August are not visible from here.

Autumn and December

Saturn reaches opposition on 18 October. The autumn showers are unlucky with the Moon: the Orionids peak on 22 October at last quarter, and the Leonids on 18 November a few days after full moon.

The Geminids, with a ZHR of about 150, are the strongest shower of the year. They are active from 4 to 20 December and peak on 14 December at around 9 p.m. CET. But full moon is on 13 December and the Moon rides high. The IMO says this will severely disturb visual observing.

The consolation is the Ursids: a small shower with a ZHR of about 10 and a peak on 23 December at 5 a.m. CET. New moon is on 27 December, so the Moon will not interfere. The radiant, near the Little Dipper, never sets here and is highest towards morning.