Event

In the Solar system, the planets follow orbits that are aligned with the Sun’s equatorial plane to within a few degrees.  But what about planets around other stars?  Many techniques are now available to measure the obliquities of planet-hosting stars, ranging from an effect predicted in the 19th century to several techniques relying on data from the Kepler space telescope.  Many exoplanetary systems show good alignment, as in the Solar system. We have also found planets on highly inclined orbits and even retrograde orbits. I will discuss the observing techniques, the patterns that have emerged from the data, and the theories that have been proposed to explain these results.