With the invention of high-temperature-superconductor, the superconductive magnetic gradiometer be-comes available in application.

由于高温超导体的研究成功，使得超导磁梯度的实际应用成为现实。

Gravity gradient is the second order derivative of gravitational potential, which can be observed by satellite gradiometer.

摘要重梯度为重位的二阶导数，可以通过星载梯度进行观。