以上内容由AI生成, 仅供参考和借鉴

1. A neutron star has a gravitational field strong enough to generate X-rays.

中子星上存在强大的重力场，足以产生X射线。

2. Its oscillation depends on the strength of the gravitational field.

它的振动幅度取决于引力场的强度。

3. the gravitational pull of the moon

月球的引力

4. Dark matter gives out no light and is detectable only because of its gravitational effect on visible matter.

暗物质不发光，它之所以能被发现，只是因为它对可见物质产生引力作用。

5. If a spacecraft travels faster than 11 km a second, it escapes the earth's gravitational pull.

如果飞行速度超过每秒11公里，宇宙飞船将摆脱地球的引力。