1.   They regard such wobbles as responses to the gravitational tugs of planets orbiting around them.

2.   As the Jovian moon begins to feel the strongest gravitational tug from Jupiter, the ice starts its first crack.

3.   Comets nudged toward the Sun by the gravitational tug of a passing star are rarely very bright on their first trip, Marsden said.

4.   Instead, they found slight wobbles in the motions of the two stars, caused by the gravitational tugs of their planets.

5.   Its presence is indicated by the gravitational tug on its parent star, which causes it to wobble enough to be recorded in spectrographic measurements of the faint starlight.

6.   The complex gravitational tugs of the two stars might preclude the process by which planets form from collapsing clouds of gas and dust, many astronomers thought.

7.   Those wobbles are caused by the extremely slight gravitational tug of a planet as it orbits the star.

8.   Tidal forces on Europa, caused by the gravitational tug of Jupiter, are highest when the moon is closest to the planet.