Related papers: Comet and Asteroid Hazard to the Terrestrial Plane…
The absolute magnitude and perihelion distributions of long-period comets are derived, using data from the Lincoln Near-Earth Asteroid Research (LINEAR) survey. The results are surprising in three ways. Firstly, the flux of comets through…
Trojan asteroids are minor planets that share the orbit of a planet about the Sun and librate around the L4 or L5 Lagrangian points of stability. They are important solar-system fossils because they carry information on early Solar System…
The outflows from comets in orbit around G-type main-sequence stars can be detected when they produce transient OH absorption lines in the spectrum near 3100 Angstroms of the host star. There is only about a 3 X 10^{-8} probability of…
The evolution of the orbits of bodies ejected from the Earth, Moon, Mercury and Mars was studied. At ejection velocities about 12-14 km/s, the fraction of bodies ejected from the Earth that fall back onto the Earth was about 0.15-0.25. The…
We compare the number of lunar craters larger than 15 km across and younger than 1.1 Ga to the estimates of the number of craters that could have been formed for 1.1 Ga if the number of near-Earth objects and their orbital elements during…
Almost half of the stellar systems in the solar neighborhood are made up of multiple stars. In multiple-star systems, planet formation is under the dynamical influence of stellar companions, and the planet occurrence rate is expected to be…
A group of newly observed extreme trans-Neptunian objects exhibit unexpected orbital confinement, characterized by the alignment of orbital angular momentum vectors and apsidal lines. It is proposed that an undiscovered giant planet, named…
Asteroid discoveries are essential for planetary-defense efforts aiming to prevent impacts with Earth, including the more frequent megaton explosions from decameter impactors. While large asteroids ($\geq$100 km) have remained in the main…
We simulate the formation and evolution of Oort clouds around the 200 nearest stars (within 16pc according to the Gaia DR2) database. This study is performed by numerically integrating the planets and minor bodies in orbit around the parent…
In this work, we performed a dynamical analysis of a spacecraft around a nearly equal-mass binary near-Earth asteroid with application to the asteroid 2017 YE5, which is also a possible dormant Jupiter-family comet. Thus, we investigated…
Circumbinary planets whose orbits become unstable may be ejected, accreted, or even captured by one of the stars. We quantify the relative rates of these channels, for a binary of secondary star's mass fraction 0.1 with an orbit of 1AU. The…
Giant impacts by comets and asteroids have probably had an important influence on terrestrial biological evolution. We know of around 180 high velocity impact craters on the Earth with ages up to 2400Myr and diameters up to 300km. Some…
The New Horizons spacecraft's nominal trajectory crosses the planet's satellite plane at $\sim 10,000\ \rm{km}$ from the barycenter, between the orbits of Pluto and Charon. I have investigated the risk to the spacecraft based on…
Among the current population of the 81 known trans-Neptunian binaries (TNBs), only two are in orbits that cross the orbit of Neptune. These are (42355) Typhon-Echidna and (65489) Ceto-Phorcys. In the present work, we focused our analyses on…
We use data from the Hipparcos Catalog and the Barbier-Brossat & Figon (2000) catalog of stellar radial velocities to test the hypothesis that the Beta Pic planetesimal disk was disrupted by a close stellar encounter. We trace the space…
Until recently, most asteroids were thought to be solid bodies whose shapes were determined largely by collisions with other asteroids. It now seems that many asteroids are little more than rubble piles, held together by self-gravity; this…
The four longest period Kuiper belt objects have orbital periods close to integer ratios with each other. A hypothetical planet with orbital period $\sim$17,117 years, semimajor axis $\sim$665 AU, would have N/1 and N/2 period ratios with…
Centaurs are minor planets orbiting between Jupiter and Neptune that have or had crossing orbits with one or more giant planets. Recent observations and reinterpretation of previous observations have revealed the existence of ring systems…
Plutinos are Kuiper-belt objects that share the 3:2 Neptune resonance with Pluto. The long-term stability of Plutino orbits depends on their eccentricity. Plutinos with eccentricities close to Pluto (fractional eccentricity difference…
The Asteroid Redirect Mission (ARM) proposes to retrieve a near-Earth asteroid and position it in a lunar distant retrograde orbit (DRO) for later study, crewed exploration, and ultimately resource exploitation. During the Caltech Space…