Central parts of comet McNaught

Imaging of the central coma of Comet McNaught. Left: a raw image taken through a filter centred on the emission by CN gas. Middle: the CN image processed using the Larson-Sekanina algorithm to reveal spiral jets of gas from the nucleus. Right: A similarly processed image of the dust in the inner coma, showing a sunward plume and the dust being swept back into the tail. The tail direction is roughly downwards in these images, which are orientated with North up and have a field of view of 2.4 arcmin on a side.