The best lines up with the geoid.

最情况是与大水准面相吻合。

And they came up with this equation that describes the geoid's contours in incredible detail.

他们出了这个方程，以令难以置信细节描述了大水准面轮廓。

So little by little, satellites refined our understanding of Earth's exact shape and this underlying geoid.

卫星一点一升了我们对球精确形状及其基础大水准面解。

Their geoid models, helped them track the exact orbits of spacecraft and satellites, in turn, helped them create better maps of Earth.

他们球模型帮助他们精确追踪航天器和卫星轨道，进而助力绘制更精准球图。