Related papers: No Death Star -- For Now
The Pioneer 10 and 11 and Voyager 1 and 2 spacecraft, launched in the 1970s, are heading out of the solar system. Using the astrometric and radial velocity data from the second Gaia data release, we integrate the trajectories of 7.4 million…
A 2000-2017 set of long-period comets with high-quality orbits of perihelion distance <1 AU is used to show that the objects that perish shortly before perihelion are nearly exclusively the Oort Cloud comets, especially those with perihelia…
Here we combine observations of open clusters (OCs) with single- and binary population synthesis models and a Galactic potential to reconstruct the SN activity of these OCs during the past 35 Myr. We find that several OCs potentially…
The dust disk detected by Pioneer at a heliocentric distance of 18 AU is a fraction of the dust generated by the Kuiper belt outside 30 AU. New Horizons will find a very high flux of more than 10 hits per day for each square meter of…
We report the discovery of two adjacent jet candidates with a length of about 9 degrees each -- 10 times longer than the largest known jets -- detected by us on 60 and 100 micron IRAS maps, but not observed at any other wavelength. They are…
For decades we have known that the Sun lies within the Local Bubble, a cavity of low-density, high-temperature plasma surrounded by a shell of cold, neutral gas and dust. However, the precise shape and extent of this shell, the impetus and…
The Sun is located in a low-density region of the interstellar medium partially filled with hot gas that is the likely result of several nearby supernova explosions within the last 10 Myr. Here we use astrometric data to show that part of…
We estimated the rate of comet and asteroid collisions with the terrestrial planets by calculating the orbits of 13000 Jupiter-crossing objects (JCOs) and 1300 resonant asteroids and computing the probabilities of collisions based on…
We calculate the expected flux profile of comets into the planetary system from the Oort cloud arising from Galactic tides and encounters with molecular clouds. We find that both periodic and sporadic bombardment episodes, with amplitudes…
We investigate the prospects for the capture of the proposed Planet 9 from other stars in the Sun's birth cluster. Any capture scenario must satisfy three conditions: the encounter must be more distant than ~150 au to avoid perturbing the…
Sungrazing comets have always captured a lot of interest and curiosity among the general public as well as scientists since ancient times. The perihelion passage of comet C/2012 S1 (ISON) at the end of this year (on 2013 November 28) is an…
The Deep Impact encounter with the nucleus of 9P/Tempel ejected small grains (a <~ 10 micron) into the comet's coma, evidenced by thermal emission from small dust grains at mid-infrared wavelengths (~10 micron) and dynamical simulations of…
We examine a low energy mechanism for the transfer of meteoroids between two planetary systems embedded in a star cluster using quasi-parabolic orbits of minimal energy. Using Monte Carlo simulations, we find that the exchange of meteoroids…
Earth occasionally crosses the debris streams produced by comets and other active bodies in our solar system. These manifest meteor showers that provide an opportunity to explore these bodies without a need to visit them in-situ.…
The Parker Solar Probe (PSP) spacecraft has flown into the most dense and previously unexplored region of our solar system's zodiacal cloud. While PSP does not have a dedicated dust detector, multiple instruments onboard are sensitive to…
Supernova explosions are one of the most energetic--and potentially lethal--phenomena in the Universe. Scientists have speculated for decades about the possible consequences for life on Earth of a nearby supernova, but plausible candidates…
The widespread detection of 60Fe in geological and lunar archives provides compelling evidence for recent nearby supernova explosions within $\sim 100$ pc around 3 Myr and 7 Myr ago. The blasts from these explosions had a profound effect on…
Unlike the Solar System planets, thousands of smaller bodies beyond Neptune orbit the Sun on eccentric ($e >$ 0.1) and ($i>$ 3$^\circ$) orbits. While migration of the giant planets during the early stages of Solar System evolution can…
Based on early solar system abundances of short-lived radionuclides (SRs), such as $^{26}$Al (T$_{1/2} = 0.74$ Myr) and $^{60}$Fe (T$_{1/2} = 1.5$ Myr), it is often asserted that the Sun was born in a large stellar cluster, where a massive…
In the latest Gaia third data release one can find extremely small proper motion components for the star HD 7977. This, together with the radial velocity measurement lead to the conclusion that this star passed very close to the Sun in the…