12p 20231006 rmiles

Thought you would like to see these images taken simultaneously earlier today through 4 filters, as per attached.

 

There are two facets that are evident:

 

One, is that given the similarity of the asymmetric feature, the eruption is most probably from the same source on July 20 as on October 6 except that it has taken place at a different stage in the rotation of the nucleus. My guess is that this is a shadowing feature caused by the body of the nucleus blocking flow over quite a large solid angle.

 

Two, is that in both cases there is a circular/spherical shell? of material about one-third the size of the main outburst coma (this also happened after July 20 but was not so apparent). Was there a second outburst in fairly quick succession, if so it should be evident in the photometry. I suspect they all started at the same time but expanded at different rates indicating a compositional difference during the course of the eruption that lasted only a few minutes before shutting down.