Spectrum of short-periodic comet 2P/Encke in the apparition of 2003

1Shubina, OS, 2Borisov, NV, 3Ivanova, OV, 4Rosenbush, VK
1Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine
2Special Astrophysical Observatory, Nizhnij Arkhyz, Russia
3Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, Astronomical Institute of Slovak Academy of Sciences, Tatranská Lomnica, Slovak Republic
4Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, Astronomical Observatory of Taras Shevchenko Kyiv National University
Kinemat. fiz. nebesnyh tel (Online) 2018, 34(4):67-80
Start Page: Dynamics and Physics of Solar System Bodies
Language: Russian

We analysed the spectra of comet 2P/Encke obtained on November 15 and 22, 2003 within the wavelength ranges 410—580 nm and 560—720 nm, with the help of the UAGS spectrograph on the 1-m telescope Zeiss-1000 of Special Astrophysical Observatory, Russian Academy of Sciences. The spectral resolution is about 0.5 nm. In the cometary coma, the emission bands of C2, CN, CH, and NH2 molecules are detected. The normalized spectral gradient of reflectivity is 11.95 ± 3.45 % per 100 nm and 7.90 ± 2.81 % per 100 nm in the wavelength bands 450—567 nm and 565—676 nm, respectively. The values of parameter Afρ = 77 ± 9, 81 ± 9, and 79 ± 9 cm for the BC, GC, and RC continuum filters, respectively, reflect a very low dust content in comet Enke. Using the Haser model, we determined the production rate of gas molecules: 1.12·1025 mol/s for C2 (Δν = 0) and 3.82·1024 mol/s for NH2 (0,10,0).

Keywords: comet, dust, spectrum

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