When a comet passes by to visit us, most of us are fascinated by the long tail of dust, often colorful, but few enter its internal structure, equally fascinating, but hidden by the high luminosity of the coma...
for to see inside, we need to process the images with specially designed filters.
Filter Larson-Sekanina:
With this command, in an astronomical image processing software, the radial and rotational gradient of an image is calculated.
It is used to highlight low-contrast details in bright objects that have a symmetrical shape of revolution (such as elliptical galaxies and comet coronas).
It is particularly powerful at detecting hidden details (such as jets or shells) within the coma of a sufficiently bright comet.