我科学家为“流浪”行星“验明正身”

Core Viewpoint - A research team led by Professor Dong Subo from Peking University has successfully measured the mass of a candidate rogue planet, confirming it to be a planet with a mass comparable to Saturn, marking a significant milestone in understanding planetary formation and dynamics [1][2]. Group 1: Research Findings - The rogue planet, which does not orbit any star and drifts in interstellar space, was identified through a gravitational microlensing event, where its gravity bent the light from a background star, causing a temporary brightening [1]. - The team utilized a unique observational opportunity on May 3, 2024, when both the KMTNet and OGLE ground telescopes detected a signal from the candidate, coinciding with the European Space Agency's Gaia satellite observations [2]. - The mass of the candidate was determined to be approximately one-fifth that of Jupiter, confirming its classification as a planet and ruling out the possibility of it being a brown dwarf or star [2]. Group 2: Implications for Future Research - This discovery indicates that rogue planets may be abundant in the Milky Way, likely ejected from their original planetary systems [2]. - The method of measuring microlensing parallax developed in this research paves the way for large-scale detection by next-generation space telescopes, such as NASA's upcoming Roman Space Telescope and China's CSST [2]. - The research highlights the importance of coordinated ground and space observations, providing a framework for future studies on the population and characteristics of rogue planets in the galaxy [2].