A NASA mission to Mercury that was launched on 3 August 2004, entered Mercury orbit on 17 March 2011, and completed its mission on 30 April 2015, when it crashed into the planet’s surface at more than 3.91 km sec−1.
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。