Even those not normally impressed with the natural sights the skies provide should make a note to look up in the next couple of days, as the International Space Station makes a series of favourable passes over Western Europe.

The station, under construction since 1998, is the largest and therefore the brightest manmade structure yet placed in orbit. It orbits the Earth once every 90 minutes or so, but the changing orbital geometry means that it is not always visible from the UK. When it is in the sky it is unmistakable, seen as a bright star which travels rapidly across the sky.

In several of the series of passes which take place over the next few nights we will see it outshine everything in the sky except Jupiter and the Moon. Perhaps the best of these passes for the casual skywatcher occur on the evenings of May 21-25. In London the best of the passes is just before midnight on the 23rd, with the station beginning low in the West at 23.56, passing almost overhead and then setting in the East at 00.02.

The times depend on your location, and there are too many passes to list here, so to get personalised predictions for your location visit the excellent www.heavens-above.com. The best passes are those which are particularly bright (at the lowest magnitude) and which have a maximum altitude close to 90 degrees.