Abstract
Spectra of comet 2P/Encke obtained on November 15 and 22, 2003, in wavelength ranges of λ = 410–580 and 560–720 nm with the Universal Astronomical Grating Spectrograph (UAGS) mounted at the 1-m Zeiss-1000 telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences is analyzed. The spectral resolution is 0.5 nm. In the cometary coma, the emission bands of C2, CN, CH, and NH2 molecules were detected. The normalized spectral gradient of the reflectivity is (11.95 ± 3.45) and (7.90 ± 2.81)% per 100 nm in wavelength bands of 450–567 and 565–676 nm, respectively. The values of the parameter Afρ are (77 ± 9), (81 ± 9), and (79 ± 9) cm for the BC, GC, and RC continuum filters, respectively, which is indicative of a very low dust content in comet Encke. With the Haser model, we determined the production rate of gas molecules at (1.12 × 1025) and (3.82 × 1024) mol/s for C2 (Δν = 0) and NH2 (0,10,0) molecules, respectively.
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ACKNOWLEDGMENTS
The work by O. Shubina was supported by the National Stipendium Program of the Slovak Republic (the SAIA project). O. Ivanova acknowledges the SASPRO Program, the Marie Curie Actions, the European Union’s Seventh Framework Program under REA grant 609427, and the Slovak Academy of Sciences (the Vega 2/2023/18 grant). We are grateful to Yu. Sizonenko and S. Borisenko for their help in the preliminary image processing and to P. Korsun for discussions on the identification of spectral emissions.
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Translated by E. Petrova
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Shubina, O.S., Borisov, N.V., Ivanova, O.V. et al. Spectrum of the Short-Period Comet 2P/Encke in the Apparition of 2003. Kinemat. Phys. Celest. Bodies 34, 207–215 (2018). https://doi.org/10.3103/S0884591318040050
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DOI: https://doi.org/10.3103/S0884591318040050