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We report on photometry and imaging of Comet 103P/Hartley 2 obtained atLowell Observatory from 1991 through 2011. We acquired photoelectric photometryon two nights in 1991, four nights in 1997/98, and 13 nights in 2010/11. Weobserved a strong secular decrease in water and all other observed speciesproduction in 2010/11 from the 1991 and 1997/98 levels. We see evidence for astrong asymmetry with respect to perihelion in the production rates of ourusual bandpasses, with peak production occurring ~10 days post-perihelion andproduction rates considerably higher post-perihelion. The composition was"typical", in agreement with the findings of other investigators. We obtainedimaging on 39 nights from 2010 July until 2011 January. We find that, afteraccounting for their varying parentage and lifetimes, the C2 and C3 comamorphology resemble the CN morphology we reported previously. These speciesexhibited an hourglass shape in October and November, and the morphologychanged with rotation and evolved over time. The OH and NH coma morphologyshowed hints of an hourglass shape near the nucleus, but was also enhanced inthe anti-sunward hemisphere. This tailward brightness enhancement did not varysignificantly with rotation and evolved with the viewing geometry. We concludethat all five gas species likely originate from the same source regions on thenucleus, but that OH and NH were derived from small grains of water and ammoniaice that survived long enough to be affected by radiation pressure and drivenin the anti-sunward direction. We detected the faint, sunward facing dust jetreported by other authors, and did not detect a corresponding gas feature. Thisjet varied little during a night but exhibited some variations from night tonight, suggesting it is located near the total angular momentum vector.

The Highly Unusual Outgassing of Comet 103P/Hartley 2 from Narrowband Photometry and Imaging of the Coma