The roughly spherical distribution of stars that forms the central hub of spiral and lenticular galaxies. The bulge is much less noticeable, relative to the disk, in the later spiral types Sc and Sd.
科学参考收录了60776条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。