Prompted by a comment published on the newsgroup [Comets-ml] about a possible outburst of comet 46P/Wirtanen reported by M. Kidger and his spanish collaborators, we performed some follow-up of this object.
Stacking of 10 unfiltered expsoures, 50 seconds each, obtained remotely from Mayhill (NM) on 2008, May 18.2 through a 0.25-m, f/3.4 reflector + CCD, show that 46P/Wirtanen currently has a very compact coma nearly 15 arcsec in diameter. The total magnitude m1 was measured to be R= 14.8. Preliminary afrho calculation provides a rather flat photometric profile with a value ranging from 90 to 130-cm for apertures diameters passing from, respectively, 10,000 to 30,000-Km at the comet distance.
Our image is available here:
by Ernesto Guido and Giovanni Sostero