gravitational method of exploration

例句：

1. 1. The gravitational pull of the earth is what keeps us on the surface of the planet.
   地球的引力作用使我们保持在星球表面。
2. 2.The gravitational force between two objects is proportional to their masses and inversely proportional to the square of the distance between them.
   两个物体之间的引力与它们的质量和它们之间的距离的平方成反比。
3. 3.The gravitational field around a star is what determines its mass and influences its behavior.
   围绕恒星的引力场决定了它的质量并影响着它的行为。