Related papers: Recent Chemo-morphological Coma Evolution of Comet…
Aims. In this work, we present an extended study of the dust environment of a sample of short period comets and their dynamical history. With this aim, we characterized the dust tails when the comets are active, and we made a statistical…
Solar wind charge-changing reactions are of paramount importance to the physico-chemistry of the atmosphere of a comet. The ESA/Rosetta mission to comet 67P/Churyumov-Gerasimenko (67P) provides a unique opportunity to study charge-changing…
Our modern day Solar System has $4.6\times10^9$ yrs of evolution behind it with just a few relics of its birth conditions remaining. Comets are thought to be some of the most pristine tracers of the initial ingredients that were combined to…
The Aswan cliff on Comet 67P/Churyumov-Gerasimenko collapsed on 2015 July 10. Thereby, relatively pristine comet material from a depth of ~12 m was exposed at the surface. Observations of the collapse site by the microwave instrument…
We present a characterization of the dust environment of long-period comet C/2023 A3 (Tsuchinshan-ATLAS) by analyzing an extensive dataset, including dust tail images and photometric measurements, from 10 au pre-perihelion to 1.6 au…
Comet 7P/Pons-Winnecke was observed from the Calar Alto Observatory (Spain) for four months during the 2021 inbound apparition. Broad-band visible images were taken between 1.71 and 1.25 AU pre-perihelion, while long-slit spectrophotometric…
The ESA Rosetta mission has acquired unprecedented measurements of comet 67/P-Churyumov-Gerasimenko (hereafter 67P) nucleus surface, whose composition, as determined by in situ and remote sensing instruments including VIRTIS (Visible,…
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…
The phase function of the dust coma of comet 67P has been determined from Rosetta/OSIRIS images \citep{Bertini17}. This function show a deep minimum at phase angles near 100$^\circ$, and a strong backscattering enhancement. These two…
In this paper, we present a unique data set of more than one year's worth of regular observations of comet C/2013 A1(Siding Spring) with TRAPPIST in Chile, along with low-resolution spectra obtained with the ESO/VLT FORS 2 instrument. The…
We identified a new ultra-distant comet C/2019 E3 (ATLAS) exhibiting preperihelion cometary activity at heliocentric distances $\gtrsim\!20$ au, making it the fourth member of this population after C/2010 U3 (Boattini), C/2014 UN$_{271}$…
Comet-centaur 29P/Schwassmann-Wachmann 1 was observed in CO+ emission and contin-uum during 2007-2009 using the 6-m Big Telescope Alt-azimuth at the Special Astrophysical Observatory of the Russian Academy of Sciences. We analysed the…
We present multi-epoch optical spectroscopy of the interstellar comet 3I/ATLAS obtained between December 2025 and January 2026 (heliocentric distances 1.8-3.3 au), yielding post-perihelion production rates and mixing ratios for CN, C$_3$,…
We investigated three comets, which are active at large heliocentric distances, using observations obtained at the 6-m BTA telescope (SAO RAS, Russia) in the photometric mode of the focal reducer SCORPIO. The three comets,…
We present imaging and spectroscopic data on comet 19P/Borrelly that were obtained around the time of the Deep Space 1 encounter and in subsequent months. In the four months after perihelion, the comet showed a strong primary (sunward) jet…
Aims. Understanding the activity is vital for deciphering the structure, formation, and evolution of comets. We investigate models of cometary activity by comparing them to the dynamics of 67P/Churyumov-Gerasimenko. Methods. We matched…
Between 2019 and 2024, we used the Gemini-N and JWST observatories to conduct a detailed case study of the active Centaur 450P/LONEOS, whose orbit was significantly altered by a close Saturn encounter in 1992. Gemini-N GMOS optical images…
In December-2025, the NASA SPHEREx spacecraft re-observed ISO 3I/ATLAS post-perihelion, finding a much more active object compared to August-2025 SPHEREx pre-perihelion observations, with marked evidence for development into an cometary…
We report on narrowband photometry and extensive imaging observations of comet C/Lulin (2007 N3) obtained at Lowell Observatory during 2008 and 2009. Enhanced CN images revealed a double corkscrew morphology with two near-polar jets…
Questions regarding how primordial or pristine the comets of the solar system are have been an ongoing controversy. In this review, we describe comets' physical evolution from dust and ice grains in the solar nebula to the contemporary…