Lab experiment mimics early-stage planetary formation process
Physicists have directly observed, for the first time, how highly charged dust-sized particles attract and capture others to build up clusters particle by particle. This process can lead to the formation of granular molecules whose configurations resemble those of simple chemical molecules. These interactions are fundamentally important in situations ranging from airborne pollutant coagulation to the clustering of dust in interstellar space. Nevertheless, a full picture of how electrostatic interactions contribute to particle aggregation has remained elusive, mainly owing to the absence of direct, in-situ experiments. In a recent paper published in the journal Nature Physics, a research team at the University of Chicago has shown how to experimentally resolve this problem. Read more
Title: Forming Different Planetary Systems Authors: J.-L. Zhou, J.-W. Xie, H.-G. Liu, H. Zhang, Y.-S. Sun
With the increasing of detected exoplanet samples, the statistical properties of planet systems become much clear. In this review, we summarise the major statistics that are revealed mainly by radial velocity and transiting observations, and try to interpret them within the scope of the classical core-accretion scenario of planet formation, especially on the formation of different orbital architectures for planet systems around main sequence stars. Based on the possible different formation routines for different planet systems, we tentatively classify they into three major catalogues: hot Jupiter system, standard system and distance-giant planet systems. The standard system can be further categorised into three sub-types under different circumstances: solar-like system, hot Super-Earth system, sub-giant planet system. We also review the planet detection and formation theory in binary systems as well as planets in star clusters.