[Buyingtime]

> In contrast, most exoplanets discovered in recent years — particularly the giants known as “hot Jupiters” — inhabit far more eccentric orbits.

I am surprised to note that Kepler data on its home page does not include estimates of planet orbit eccentricity. They could. Admittedly some of the eccentricity data is indistinguishable from orbital inclination, but if the assumption of a circular orbit is incompatible with transit time then this gives a limit on orbit eccentricity.

Come to think of it, I could calculate it myself, from transit duration, stellar radius and period. Perhaps some other time.

Even more to the point, I could also use this to look into why there are so incredibly few Kepler candidates with orbital periods greater than Earth's.

> That has often crossed my mind and had me wondering how they can tell the difference between say a planetary transit and a "Sun/star spot" for a distant stellar object.

Worried me for a while, but now I'm sure they have it right. The shape of the light curve dip for a sunspot doesn't have a sharp edge like that of a planet, and a sunspot doesn't last as long at constant brightness. Most of the "false positives", and there have been thousands of them, are due to triple stars.

I don't see any data for stellar rotation speed in the Kepler data, surely they could get that from sunspots.