Starwatch: a subtle shadow on the face of the moon

Less spectacular than a total eclipse but no less interesting, the penumbral lunar eclipse to be seen on Friday will be well worth watching

This week's astronomical event will be easy to see but hardly anyone will notice it. On 5 June, the full moon will clip the outer portion of Earth's shadow, creating a penumbral lunar eclipse. This is much subtler than a total lunar eclipse, in which the moon appears to turn red as it passes through the darkest part of Earth's shadow, situated right behind our planet. Penumbral lunar eclipses are difficult to discern by eye because only a portion of the sun's light is blocked from reaching the moon.