Related papers: 1I/2017 U1 (Oumuamua) Might Be A Cometary Nucleus
The IceCube neutrino telescope has observed for the first time a diffuse flux of high energy neutrinos, with a possible astrophysical origin. Up to now there are no evidence of sources and many hypothesis are still plausible in order to…
The IceCube evidence for cosmic neutrinos has inspired a large number of hypothesis on their origin, mainly due to the poor precision on the measurement of the direction of showering events. A North/South asymmetry in the present data set…
Some gamma ray bursts may be produced by supernovae exploding in close massive binary systems (type Ib/c supernovae) as suggested by the recent observation of SN 1998bw/GRB 980425. We propose that high energy radiation observed in such…
Comets are considered as the most primitive objects in the Solar System. Their composition provides information on the composition of the primitive solar nebula, 4.6 Gyr ago. The radio domain is a privileged tool to study the composition of…
This is a review of high energy neutrino astronomy that might be done with a kilometer-scale detector. The emphasis is on diffuse neutrinos of extragalactic origin and their relation to possible sources of the highest energy cosmic rays,…
Main Belt comets represent a recently discovered class of objects. They are quite intriguing because, while having a Tisserand invariant value higher than 3, are showing cometary activity. We study the activity of the Main Belt comets…
Topic of this work are comets, small and elusive objects that may hold great secrets about the origin of the Solar System and life on Earth, being among the most primitive objects. The method of investigation addressed in this work is the…
The stellar halo contains some of the oldest stars in the Milky Way galaxy and in the universe. The detections of `Oumuamua, CNEOS 2014-01-08, and interstellar dust serve to calibrate the production rate of interstellar objects. We study…
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.…
In this review presented at the Royal Society meeting, "Cometary Science After Rosetta", I present an overview of studies of small solar system objects that exhibit properties of both asteroids and comets (with a focus on so-called active…
We summarize the theoretical description of wave packets on molecular energy levels. We review the various quantum mechanical effects which can be studied and the models that can be verified on this system. This justifies our claim that the…
The assumption that short-period (SP) comets are fragments of massive icy envelopes of Ganymede-like bodies saturated by products of ice electrolysis that underwent global explosions provides a plausible explanation of all known…
Comet nuclei in the outer Solar system are constantly irradiated by cosmic rays at low temperatures. Accumulated high concentrations of radicals can undergo fast recombination with significant heating of cometary surface layers. We present…
We present observations of main-belt comet 358P/PANSTARRS (P/2012 T1) obtained using the Gemini South telescope from 2017 July to 2017 December, as the object approached perihelion for the first time since its discovery. We find best-fit…
The Fermi bubbles, two giant structures above and below the Galactic center (GC), are among the most important discoveries of the Fermi Gamma-ray Space Telescope. Studying their physical origin has been providing valuable insights into…
A circumsolar dust ring has been recently discovered close to the orbit of Mercury. There are currently no hypotheses for the origin of this ring in the literature, so we explore four different origin scenarios here: the dust originated…
2I/Borisov is the second interstellar object (ISO) after 'Oumuamua (Meech et al. 2017), but differs from 'Oumuamua drastically with its extensive cometary activity. A key ingredient to understand the nature of this comet is its size.…
FS CMa type stars are a group of Galactic objects with the B[e] phenomenon. They exhibit strong emission-line spectra and infrared excesses, which are most likely due to recently formed circumstellar dust. The group content and…
Observational cosmology is on the verge of new discoveries that will change the essence of our world-view. The matter concerns origin of initial conditions and physics of dark matter.
A fundamental question in cometary science is whether the different dynamical classes of comets have different chemical compositions, which would reflect different initial conditions. From the ground or Earth orbit, radio and infrared…