Production rates for the Stardust mission target:: 81P/Wild 2

We observed 81P/Wild 2 from February 01 to June 01, 1997, during five observing runs spaced roughly 1 month apart straddling perihelion 1997 May 06.6. A considerable volume of spectroscopic data was collected and is analyzed in the present paper. In units of 10(25) molecules/s the following gas production rates were measured: H2O, 1500; CN, 3.3; NH2, 4.0; C-2, less than or equal to 0.9. Emissions by C-2 appear to be present in our data but this is not certain. The gas production stayed relatively constant throughout our observation period but the dust production as measured by Afp dropped from 564 to 311 cm. Comparison with other comets in our sample shows that Wild 2 is a Borrelly-type comet depleted in C-2, but with average to slightly high NH2 abundance. Our imaging data indicate noticeable coma activity around February 01 followed by relatively constant outgassing. Our V + R magnitudes are compared with visual data and their different behavior is discussed and explained. The comet's visual magnitude brightness dependence shows a steep 25 log r(H) dependence, indicating a mature crust. (C) 1999 Academic Press.