Related papers: Comet and Asteroid Hazard to the Terrestrial Plane…

The Oort cloud is usually thought of as a collection of icy comets inhabiting the outer reaches of the Solar system, but this picture is incomplete. We use simulations of the formation of the Oort cloud to show that ~4% of the small bodies…

The recent publication by Siraj & Loeb (2021; Nature Scientific Reports 11, 3803) attempts to revive the debate over whether the Chicxulub impactor was a comet or an asteroid. They calculate that ~20% of long-period comets impacting Earth…

The problem of the formation of the Moon is still not explained satisfactorily. While it is a generally accepted scenario that the last giant impact on Earth between some 50 to 100 million years after the starting of the formation of the…

In most extrasolar planetary systems, the present orbits of known giant planets admit the existence of stable terrestrial planets. Those same giant planets, however, have typically eccentric orbits that hint at violent early dynamics less…

Collisions are one of the key processes shaping planetary systems. Asteroid families are outcomes of such collisions still identifiable across our solar system. The families provide a unique view of catastrophic disruption phenomena and…

The TRAPPIST-1 system is unique in that it has a chain of seven terrestrial Earth-like planets located close to or in its habitable zone. In this paper, we study the effect of potential cometary impacts on the TRAPPIST-1 planets and how…

The recent discovery of a planet in an orbit with eccentricity $e = 0.63 \pm 0.08$ around the Solar-type star 16 Cyg B, together with earlier discoveries of other planets in orbits of significant eccentricity, raises the question of the…

This paper presents synthetic observations of long-lived, coorbiting asteroids of Mercury, Venus, the Earth and Mars. Our sample is constructed by taking the limiting semimajor axes, differential longitudes and inclinations for long-lived…

Planetary systems formed in clusters may be subject to stellar encounter flybys. Here we create a diverse range of representative planetary systems with different orbital scales and planets' masses and examine encounters between them in a…

The search for planets orbiting other stars has recently expanded to include stars from galaxies outside the Milky Way. With the TESS and Gaia surveys, photometric and kinematic information can be combined to identify transiting planet…

The aim is to show that in case of low probability of asteroid collision with Earth, the appropriate selection and weighing of the data are crucial for the impact investigation, and to analyze the impact possibilities using extensive…

Motivated by the report of a possible new planetary member of the Solar System, this work calculates cross sections for interactions between passing stars and this proposed Planet Nine. Evidence for the new planet is provided by the orbital…

Continuous habitability of a planet is a critical condition for advanced forms of life to appear, but it can be endangered by astronomical events such as stellar encounters. The purpose of this study is to analyze close stellar encounters…

For many years, it was assumed that Jupiter prevented the Earth from being subject to a punishing impact regime that would greatly hinder the development of life. Here, we present the 4th in a series of studies investigating this…

I find evidence for clustering in age of well-dated impact craters over the last 500 Myr. At least nine impact episodes are identified, with durations whose upper limits are set by the dating accuracy of the craters. Their amplitudes and…

Passing stars can perturb the Oort Cloud, triggering comet showers and potentially extinction events on Earth. We combine velocity measurements for the recently discovered, nearby, low-mass binary system WISE J072003.20-084651.2 ("Scholz's…

The discovery of Sedna places new constraints on the origin and evolution of our solar system. Here we investigate the possibility that a close encounter with another star produced the observed edge of the Kuiper belt, at roughly 50 AU, and…

Stars formed in clusters can encounter other stars at close distances. In typical open clusters in the Solar neighbourhood containing hundreds or thousands of member stars, ten to twenty per cent of Solar-mass member stars are expected to…

Centaurs--icy bodies orbiting beyond Jupiter and interior to Neptune--are believed to be dynamically related to Jupiter Family Comets (JFCs), which have aphelia near Jupiter's orbit and perihelia in the inner Solar System. Previous…

We present the overall statistical results from the Robo-AO Kepler planetary candidate survey, comprising of 3857 high-angular resolution observations of planetary candidate systems with Robo-AO, an automated laser adaptive optics system.…