Passage Summary: Many distant planets have oval orbits, unlike our circular ones. Since comets in our system get oval orbits from getting too close to planets, maybe those distant planets got their oval orbits the same way—by getting too close to other planets.

Conclusion: Some planets with oval orbits around distant stars were likely pushed into those shapes by interactions with other planets in their systems.

Reasoning: In our own solar system, many comets have been forced into oval orbits due to close encounters with planets.

Analysis: The astronomer is using an analogy between comets and planets to explain orbital shapes. To strengthen this, we need to make the comparison more robust or provide evidence that the necessary conditions for this 'pushing' exist elsewhere. An answer that suggests these distant stars typically have multiple planets would be very helpful, as you can't have a 'close encounter' with another planet if there isn't one there. Alternatively, look for an answer that confirms the physics of orbital changes works similarly for both small bodies like comets and large bodies like planets.