Related papers: A Dormant Captured Oort Cloud Comet Awakens: (1891…
Comet ATLAS (C/2024 S1) is a bright dwarf sungrazer, the second Kreutz comet discovery from the ground this century, 13 years after comet Lovejoy (C/2011 W3). The Population II membership of comet ATLAS sets it apart from the overwhelming…
Dust jets, i.e. fuzzy collimated streams of cometary material arising from the nucleus, have been observed in-situ on all comets since the Giotto mission flew by comet 1P/Halley in 1986. Yet their formation mechanism remains unknown.…
We investigate the possible origins of real high-inclination Centaurs and trans-neptunian objects using a high-resolution statistical search for stable orbits that simulates their evolution back in time to the epoch when planet formation…
We present the analysis of microlensing event OGLE-2014-BLG-0221, a planetary candidate event discovered in 2014. The photometric light curve is best described by a binary-lens single-source model. Our light curve modeling finds two…
The close encounter of Comet C/2013 A1 (Siding Spring) with Mars on October 19, 2014 presented an extremely rare opportunity to obtain the first flyby quality data of the nucleus and inner coma of a dynamically new comet. However, the…
We present CCD VR_C observations of 6 distant comets located at heliocentric distances of 3.4--7.2 AU. Time-series data were obtained on three nights in July, 2000 covering 16 hours. Each comet was observed after the perihelion, when a…
We present a numerical simulation of the dynamical interaction between the proposed Planet Nine and a debris disk around the Sun for $4{\rm Gyr}$, accounting for the secular perturbation of the four giant planets in two scenarios: (a) an…
It is well known that some Main Belt asteroids show comet-like features. A representative example is the first known Main Belt comet 133P/(7968) Elst-Pizarro. If the mechanisms causing this activity are too weak to develop visually evident…
The Advanced LIGO and Virgo gravitational wave observatories detected a signal on 2019 August 14 during their third observing run, named GW190814. A large number of electromagnetic facilities conducted follow-up campaigns in the search for…
Several lines of observational evidence suggest that white dwarfs receive small birth kicks due to anisotropic mass loss. If other stars possess extrasolar analogues to the Solar Oort cloud, the orbits of comets in such clouds will be…
Over the past two decades, an increasing number of transients have shown luminous activity at their explosion sites weeks to years before an interacting supernova (SN) is observed. For some objects, this pre-SN activity is typically linked…
The paper deals with several properties of the Oort cloud of comets. Sun, Galaxy (and Jupiter) gravitationally act on the comets. New physical model of galactic tide is considered. The main results can be summarized as follows: 1. Mass of…
The 24 M Jupiter mass brown dwarf 2MASS1207-3932 has for some time been known to show clear signs of classical T Tauri-like accretion. Through analysis of its oxygen forbidden emission we have discovered that it is driving a bipolar…
Comet C/2016 R2 PanSTARRS (hereafter C/2016 R2) presents an unusually high N2/CO abundance ratio, as well as a heavy depletion in H2O, making it the only known comet of its kind. Understanding its dynamical history is therefore of essential…
Although the majority of Centaurs are thought to have originated in the scattered disk, with the high-inclination members coming from the Oort cloud, the origin of the high inclination component of trans-Neptunian objects (TNOs) remains…
We report the discovery of a dwarf planet candidate, 2017 OF201, currently located at a distance of 90 au. Its orbit is extremely wide and extends to the inner Oort cloud, with a semi-major axis of 830 au and a perihelion of 45 au,…
Explaining the origin of the orbit of 2000 CR105 (a ~ 230AU, q ~ 45AU) is a major test for our understanding of the primordial evolution of the outer Solar System. Gladman et al. (2001) showed that this objects could not have been a normal…
Molecular clouds around a run-away O star z Oph have been surveyed with NANTEN telescope and their streaming motion caused by z Oph has been detected. z Oph is the earliest member of the Sco OB2 association and is a runaway star rapidly…
The Oort Cloud, the Kuiper Belt and the Scattered Disk are dynamically distinct populations of small bodies evolving in the outer regions of the Solar System. Whereas their collisional activity is now quiet, gravitational interactions with…
The Centaurs are recent escapees from the Kuiper belt that are destined either to meet fiery oblivion in the hot inner regions of the Solar system or to be ejected to the interstellar medium by gravitational scattering from the giant…