the GRAIL mission, twin spacecraft due to measure the Moon's gravitational field;

还有“圣杯”的使命，孪生的飞船将会测量月球的重力场；

youdao

the GRAIL mission, twin spacecraft due to measure the Moon's gravitational field;

还有“圣杯”的使命，孪生的飞船将会测量月球的重力场；

youdao