88.Now,scientistshave data from satellites and ground—based observations from which we know that the auroral brilliance isan immense electrical discharge similar to that occurring in a neon sign.
(介词提前的定语从句:from which,which指前面的data)
如今,科学家们根据来自卫星和陆基观察的数据得知,极光是发光原理类似于霓虹灯的巨大的电流释放。
解析:
主句:scientistshave data from satellites and ground—based observations
从句1:from which we know
从句2:the auroral brilliance is animmense electrical discharge
从句3:similar to that occurring in a neonsign
从句1修饰主句中的data
从句2作为从句1的宾语从句,表示科学家从data中的得知的内容
从句3修饰从句2整句