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We monitor the inner coma of comet 41P/Tuttle-Giacobini-Kres{a}k searching for variations of its colour. Fast changes in colour of the comet 41P/Tuttle-Giacobini-Kres{a}k provide important clues for better understanding of the microphysical properties of its dust. Using the 61-cm and 70-cm telescopes we measured the apparent magnitude of the comet with the V and R Johnson-Cousins filters from January 29 until April 25 of 2017. The inner coma ({sim} 2000 km) reveals fast and significant variations of colour. The most significant change was found between March 3 and 4 of 2017, when it changed from blue with a colour slope S {approx}(-10.15 {pm} 3.43){%} per 0.1 {mu}m to red with S {approx} (16.48 {pm} 4.27){%} per 0.1 {mu}m. This finding appears in good accordance with what was previously reported by Ivanova et al. (2017) for long-period comet C/2013 UQ4 (Catalina), suggesting that fast and significant variations of colour of dust could be a common feature of short- and long-period comets. We model observations of comet 41P/Tuttle-Giacobini-Kres{a}k using the agglomerated debris particles and conclude that its inner coma consists of a mixture of at least two types of particles made of Mg-rich silicates and organics or Mg-Fe silicates.
Cometary outgassing can produce torques that change the spin state of the nucleus, influencing the evolution and lifetimes of comets (1,2). If these torques spin up the rotation to the point that centripetal forces exceed the material strength of the
Thanks to the Rosetta mission, our understanding of comets has greatly improved. A very good opportunity to apply this knowledge appeared in early 2017 with the appearance of the Jupiter family comet 41P/TGK. We performed an observational campaign wi
Comet 41P/Tuttle-Giacobini-Kresak (41P), a Jupiter family comet with three discoveries over about 100 years, is in a short-periodic orbit around the Sun with the perihelion close to the Earth distance. The 2017 apparition of 41P offered a long-lastin
We report on photometry and imaging of the Jupiter Family Comets 41P/Tuttle-Giacobini-Kresak and 45P/Honda-Mrkos-Pajdusakova with the TRAPPIST-North telescope. We observed 41P on 34 nights from February 16, 2017 to July 27, 2017 pre- and post-perihel
We report results of polarimetric observations of comet 21P/Giacobini-Zinner made at phase angles, {alpha}=76-78 deg, between 10 and 17 of September 2018, and compare them with previous measurements. We find significant variations in the polarimetric