Related papers: Initial characterization of interstellar comet 2I/…

The first known interstellar object, 1I/2017 U1 'Oumuamua, displayed such unusual properties that its origin remains a subject of much debate. We propose that 'Oumuamua's properties could be explained as those of a fractal dust aggregate (a…

Comets are primitive remnants of the early Solar System whose composition offers fundamental clues to their formation and evolution. High-resolution, broad-wavelength spectroscopy is crucial for identifying volatile species and constraining…

Comet C/2012 S1 (ISON) shows strange photometric behavior compared to many past comets. Shortly after its discovery, majority of astronomers expected its surviving until perihelion passage. Unprecedented evolution of its photometric…

3I/ATLAS is only the second confirmed cometary object known to enter the Solar System from interstellar space. Cosmogonic considerations suggest that this body may possess relatively high tensile strength and a substantial metal fraction.…

We report on the detection of three icy cavities on the nucleus of comet 67P/Churyumov-Gerasimenko. They were identified on high-resolution anaglyphs built from images acquired by the OSIRIS instrument aboard the Rosetta spacecraft on 2016…

Orbital elements of C2011 L4 (PanStarrs) Oort cloud comet, computed by MPC (Minor Planet Center, Minor Planet Electronic Circular 2012-T08), show that the closest approach to the Sun occurred on 2013 March 10th, at about 0.3 A.U., then…

Oumuamua, the first known object of extrasolar origin seen to enter our Solar System, has multiple unusual characteristics that, taken together, are very difficult to explain with conventional astronomical entities like asteroids and…

The detections of 1I/Oumuamua and 2I/Borisov within just two years demonstrate impressively that interstellar objects (ISOs) must be common in the Milky Way. Once released from their parent system, these ISOs travel for Gyr through…

3I/ATLAS is the third interstellar comet identified as passing through the Solar System. Its high outgassing activity and favourable perihelion passage on October 29, 2025 UT provided an excellent opportunity to investigate the composition…

We present a photometric and dynamical study of comet C/2010 U3 (Boattini), which was seen active in prediscovery data as early as 2005 November at a new inbound record heliocentric distance $r_{\rm H} = 25.8$ au. Two outburst events around…

With the recent discoveries of interstellar objects `Oumuamua and Borisov traversing the solar system, understanding the dynamics of interstellar objects is more pressing than ever. These detections have highlighted the possibility that…

Comet C/2020 V2 (ZTF) is categorized as a dynamically new long-period comet, making its first approach to the inner Solar system. We have observed this comet for around 32 months (from January 2022 to July 2024) at heliocentric distances…

We examine meteoroid orbits recorded by the Canadian Meteor Orbit Radar (CMOR) from 2012-2019, consisting of just over 11 million orbits in a search for potential interstellar meteoroids. Our 7.5 year survey consists of an integrated…

Comet C/2013 US10 (Catalina) was an dynamically new Oort cloud comet whose apparition presented a favorable geometry for observations near close Earth approach (~0.93au) at heliocentric distances ~2au when insolation and sublimation of…

Aims. The Alice far-ultraviolet spectrograph onboard Rosetta is designed to observe emissions from various atomic and molecular species from within the coma of comet 67P/ Churyumov-Gerasimenko and to determine their spatial distribution and…

We report the detection of the nucleus of interstellar object 3I/ATLAS, using a nucleus extraction technique on Hubble Space Telescope (HST) observations taken between December 2025 and January 2026. The product of the V-band geometric…

We present 2-5 $\mu$m spectroscopic observations of the dust coma of 67P/Churyumov-Gerasimenko obtained with the VIRTIS-H instrument onboard Rosetta during two outbursts that occurred on 2015, 13 September 13.6 h UT and 14 September 18.8 h…

We present an occultation study of compact radio sources by the plasma tail of interstellar Comet 2I/Borisov (C/2019 Q4) both pre- and near-perihelion using the Arecibo and Green Bank radio telescopes. The interplanetary scintillation (IPS)…

We present an analysis of the photometric and spectroscopic data of the comet C/2012 S1 (ISON) observed at the heliocentric distances of 6.21\div 4.81 AU. The photometric observations were made with the 60-cm Zeiss-600 telescope (ICAMER,…

Recent measurements carried out at comet 67P/C-G with the ${\it Rosetta}$ probe revealed that molecular oxygen, O$_2$, is the fourth most abundant molecule in comets. Models show that O$_2$ is likely of primordial nature, coming from the…