相关论文: Configuration of Single Giant Planet Systems Gener…

Planets are formed from collisional growth of small bodies in a protoplanetary disk. Bodies much larger than approximately $1$\,m are mainly controlled by the gravity of the host star and experience weak gas drag; their orbits are mainly…

Observations indicate that the gaseous circumstellar disks around young stars vary significantly in size, ranging from tens to thousands of AU. Models of planet formation depend critically upon the properties of these primordial disks, yet…

Experience shows that celestial bodies have a nearly round shape only from a certain size. At IAU resolution B5, item b, that shape serves as an indicator for a distinct mechanism of its forming, caused by a minimum of mass. Rigid body…

Discovered in October 2017, the interstellar object designated 1I/'Oumuamua was the first such object to be observed travelling through our solar system. 1I/'Oumuamua has other characteristics never seen before in a celestial body and…

In October 2017, the first interstellar object within our solar system was discovered. Today designated 1I/'Oumuamua, it shows characteristics that have never before been observed in a celestial body. Due to these characteristics, an…

We investigate the trapping of interstellar objects during the early stages of star and planet formation. Our results show a very wide range of possible values that will be narrowed down as the population of interstellar objects becomes…

We explore what may be learned by close encounters between extrasolar minor bodies like `Oumuamua and the Sun. These encounters may yield strong constraints on the bulk composition and possible origin of `Oumuamua-like objects. We find that…

Celestial bodies with a mass of M ~ 10 M_Jup have been found orbiting nearby stars. It is unknown whether these objects formed like gas-giant planets through core accretion or like stars through gravitational instability. I show that…

The phenomenon of 1I/'Oumuamua introduced the interstellar object (ISO) class of celestial body into the astronomical lexicon, those objects with heliocentric speeds clearly in excess of that required to parabolically escape the Solar…

Planet formation around one component of a tight, eccentric binary system such as $\gamma$ Cephei (with semimajor axis around 20 AU) is theoretically challenging because of destructive high-velocity collisions between planetesimals. Despite…

The locations of the fully despun, double synchronous end states of tidal evolution are derived for spherical components. With the exception of nearly equal-mass binaries, binary asteroid systems are in the midst of lengthy tidal…

The Atacama Large Millimeter/submilimeter Array (ALMA) recently revealed a set of nearly concentric gaps in the protoplanetary disk surrounding the young star HL Tau. If these are carved by forming gas giants, this provides the first set of…

The optical images of near-Earth asteroid 4179 Toutatis acquired by Chang'e-2 spacecraft show that Toutatis has an elongated contact binary configuration, with the contact point located along the long axis. We speculate that such…

In the standard formation models of terrestrial planets in the solar system and close-in super-Earths in non-resonant orbits recently discovered by exoplanet observations, planets are formed by giant impacts of protoplanets or planetary…

Direct imaging searches have begun to detect planetary and brown dwarf companions and to place constraints on the presence of giant planets at large separations from their host star. This work helps to motivate such planet searches by…

After reviewing the difficulties faced by the conventional theory of planet formation (based upon the aggregation of microscopic dust particles), we describe an alternative hypothesis. We propose that planets form by gravitational collapse…

The discovery that many trans-neptunian objects exist in pairs, or binaries, is proving invaluable for shedding light on the formation, evolution and structure of the outer Solar system. Based on recent systematic searches it has been…

Panspermia is the hypothesis that life originated on Earth from the bombardment of foreign interstellar ejecta harboring polyextremophile microorganisms. Since the 2017 discovery of the interstellar body 'Oumuamua (1I/2017 U1) by the…

Direct imaging observations of planets revealed that wide-orbit ($>10$ au) giant planets exist even around subsolar-metallicity host stars and do not require metal-rich environments for their formation. A possible formation mechanism of…

The two innermost planets of the Proxima Centauri system are separated by just 0.02 au, inducing strong gravitational interactions between them. We assess this interaction by leveraging fast orbital stability indicators and find that…