No dia 17 de junho foi publicado o artigo "BVR photometry of comets 63P/Wild 1 and C/2012 K1 (PANSTARRS)" na revista "Astrophysics and Space Science". Neste trabalho, fizemos uma analíse de dados obtidos com telescópios em três continentes. Muitas imagens previamente divulgadas neste blog dos cometas 63P e K1 foram usadas neste trabalho. Obtivemos os períodos de rotação nuclear, nível de coesão estrutural, parâmetros morfológicos e cores das comas destes dois cometas. O resumo do artigo é apresentado abaixo:
"We analyzed BVR photometry of comets 63P/Wild 1 and C/2012 K1 (PANSTARRS) imaged between March 2013 and May 2014 with telescopes ranging from 0.20 m to 2.0 m aperture in Australia, Europe, and the United States. We found R-band nuclear magnitudes H0=16.3±0.6 and 12.52±0.02 for comets 63P and K1, respectively. With a geometric albedo of 0.04, the nuclei have radii of 1.5±0.4 and 8.67±0.08 km, respectively. Using the Lomb-Scargle periodogram, we found that the most likely rotation periods of these nuclei are 14±2 h and 9.4±0.4 h, with peak-to-peak light curve amplitudes of 0.85±0.01 and 0.4±0.2 magnitudes, respectively. The inner coma of both comets was probably optically thin and in steady state during our observations. The average normalized reflectivity gradient S' of the coma of 63P and K1 is 10±15 (1σ) and 8±7%/100 nm in the spectral range between 440 and 647 nm, indicating that both comets are statistically redder than the Sun. The Kruskal-Wallis H-test indicates that the distribution of the B-V, V-R, and B-R color indices of the objects is similar, indicating some similarity in the physical or mineralogical properties of the comas of these comets."
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| Curvas de luz rotacionais do cometas 63P e K1. |
Você pode encontrar algumas imagens usadas neste artigo nos seguintes links: 63P (1 e 2) e K1 (1, 2 e 3).
