Are planets with highly elliptical orbits easier to detect than ones in circular orbits?
The thing that makes planets detectable with modern spectroscopic techniques is that the way the planets perturb the velocity of their star varies in a periodic manner over the space of a few years. Any longer, and you do not have enough data to follow the motion through a complete orbit and see it re-occur in successive cycles. The mass of the planet and its distance from the star greatly influence the amplitude of the velocity change you are looking for, and this also makes planets easily detectable. So, the most favored planets have orbits of about a few years or less, and masses about that of Jupiter or more, and not too highly elliptical. If the orbits are highly elliptical, you might be able to detect the planet’s velocity perturbation as it makes its close approach to the star ( periastron), but not be able to detect the planet at its farthest point in the orbit. You would therefore not have a clear trace of the periodic orbit in the data. The computer programs being used to hun
