Further fragmentation events in 213P/Van Ness

Stacking of 9 R-filtered exposures, 120-sec each, obtained remotely, from the Siding Spring-Faulkes Telescope South on 2011, September 20.6, through a 2.0-m f/10.0 Ritchey-Chretien + CCD, shows that fragment b of comet 213P is still visible, albeit very faint and diffuse (m2 about 21.5, coma diameter about 5-arcsec). Fragment b was located about 5.7 arcmin in PA 240 respect the main nuclear condensation of 213P/Van Ness.

During the same observing session, we noticed also the presence of a new fragment, not visible on our past images obtained with the same set-up (the last of which dates back 2011, Sep. 2.5): this additional fragment (that we called below "part-y") appears slightly brighter and compact than 0213Pb itself (m1 about 21.0, coma diameter about 4-arcsec elongated toward the southwest). "part-y" was located about 4.5 arcmin in PA 239 respect the main nuclear condensations of 213P/Van Ness.

We obtained additional follow-up through the same instrumentation on 2011, Sep. 21.6, confirming the existence of both fragments b and "part-y". Further inspection of our images, exclude the presence of other fragments brighter than magnitude R about 22, up to 12-arcmin tailward of 213P.

by Giovanni Sostero, Ernesto Guido & Nick Howes