Serpens is an oddity: the only constellation interrupted by another. Half way down the serpent it crosses Ophiuchus and finishes on the other side of this constellation.

There is, however, a reason for this interruption. Ophiuchus is known as ‘the serpent holder’. He was also a mythical healer, an ancient medical man. The constellation representing Ophiuchus shows him grasping the serpent, which is therefore spread across the body of Ophiuchus.

In fact, the snake that Ophiuchus is holding has entered modern medicine as the symbol of medicine, known as the caduceus: a staff with two winding snakes.

And so when we study Serpens we'll also have to recognise at least part of Ophiuchus.

The constellation has some fine binaries for binoculars as well as two Messier objects, both star clusters.

Prerequisite: Corona Borealis.

Click on any orange-coloured object.