Full lunar eclipse visible in Belgium on Friday night

This Friday (27 July) won't just be the hottest day of the year so far - it's also your chance to see the longest full lunar eclipse in a century.

The eclipse should be visible in Belgium from about 21.30 until shortly after midnight. In contrast to a solar eclipse, there is no danger in looking at a lunar eclipse. All you need is your eyes, a clear sky and a notion of the right time and direction to look up.

The Mira observatory in Grimbergen, just outside Brussels, is one of several in Belgium opening its doors to the public for the occasion. It will also be live-streaming a video of the event.

A lunar eclipse takes place when the sun, the earth and the moon line up in such a way that the moon lies entirely in the earth's shadow. When this happens, the only light to reach the moon's surface first passes through the earth's atmosphere. This sometimes makes the moon look red, hence the term "blood moon".

There are between four and seven eclipses every year around the world. Solar eclipses, when the moon comes between the sun and the earth, are short-lived and only visible in a narrow band of locations. Lunar eclipses last longer and can be seen from a wider range of places, but even so Western Europe sometimes misses out.

Another total lunar eclipse will visible in Belgium on 21 January 2019, but this is an unusually short gap. After that the wait for the next one is longer, until 16 May 2022, followed by 7 September 2025.