The galaxy M63 (NGC 5055) in Canes Venatici. It is a 9th-magnitude spiral midway between types Sb and Sc. The estimated distance is 30–35 million l.y.
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。