中文摘要：

通过对位于银河系中心的非热、致密射电源人马座A^＊（Sagittarius A^＊）的高分辨率甚长基线干涉（VLBI）观测,文章作者及其合作者成功地得到人马座A＊的固有辐射区域的直径仅为1个天文单位,支持其是超大质量黑洞的物理解释.文章在较详细地介绍此研究的同时,也简要提及了从黑洞概念的最早提出至今的200多年里人们在黑洞物理认知上的一些重大进展.可以预期,未来亚毫米波VLBI观测将有望揭示银河系中心超大质量黑洞的阴影结构.

英文摘要：

With the high-resolution millimeter-VLBI observations, we have determined an intrinsic size of the radio-emitting region of the galactic center compact nonthermal radio source Sagittarius A ＊ （ Sgr A ＊ ） of only 1 AU in diameter at 3.5mm, strongly supporting its supermassive black hole nature. A full description of this work is given, along with a brief historical overview of our understanding of black hole physics over the past two centuries since the concept of black holes was first pursued in 1783. Future sub-millimeter VLBI observation is promising for revealing the fine structure of the shadow of the galactic center black hole.