星空有约丨宇宙神秘“小红点”为何那么红？我国科学家提出新解释

Core Viewpoint - The James Webb Space Telescope has discovered a large number of small, bright red celestial bodies, referred to as "small red dots," which differ from previously identified galaxies and have puzzled astronomers [1][2]. Group 1: Discovery and Characteristics - The "small red dots" are numerous, densely structured, and exhibit a very red color, challenging existing astronomical theories [1]. - Traditional models assumed that the red appearance was due to significant amounts of interstellar dust causing a "reddening" effect, but observations show these celestial bodies contain very low dust levels [1][2]. Group 2: Proposed Mechanism - A research team led by Professor Wu Qingwen proposed a new physical mechanism explaining the red color, attributing it to the radiation from the outer regions of the supermassive black hole's accretion disk, which falls within the visible to near-infrared spectrum [2]. - The outer accretion disk is in a quasi-stable state with a relatively low temperature (approximately 2000 to 4000 degrees Celsius), while the inner disk reaches temperatures exceeding 10,000 degrees Celsius, resulting in a "V"-shaped spectral energy distribution that aligns with the observations from the James Webb Space Telescope [2]. Group 3: Implications for Galaxy Evolution - The findings suggest that in the early universe, some smaller galaxies may have formed only supermassive black holes and stellar clusters at their centers, with weak large-scale star formation, leading to the visibility of only the core regions [2]. - Over billions of years, as galaxies grow, the formation and death of stars in the core create significant amounts of dust, transitioning the "small red dots" into ordinary galaxies, providing critical insights into the early evolution of galaxies and black holes [2].