They return regularly to the surface (when the data is sent via polar-orbiting satellites) and are untroubled by surfaceice.
它们会定期返回到水面——这时数据将通过极地轨道卫星发送出去——并且不会受到表面冰层的困扰。
2
The answer, the scientists suspect: when Eris comes closer to the sun in its highly elongated orbit, surfaceice warms up to form a temporary atmosphere.
科学家们怀疑，它的答案是：在厄里斯在它极为扁长的轨道运行接近太阳时，表面冰变暖而形成了暂时的大气。
3
The culprit, according to a new study, is the Arctic's receding surfaceice, which at current rates of decline could disappear entirely during summer months by century's end.