fast imaging; Kepler

I spent a bit of the morning interviewing Wolfgang Brandner (MPIA) about Astralux, their fast imaging camera (no longer Lucky Imaging camera since we are going to get everyone using The Thresher). We talked about how the fast cameras work; I learned that they have significant non-linearity and saturation can be a problem. The first has been corrected (how well, I wonder?) and the second we would need to take into account at Threshing. We also discussed the possibility (which is hard to deal with) that the same atmospheric variations that create a non-trivial PSF can also create plate-scale variations. Not sure whether to think about that; we do see some evidence for that in the data we have.

In the afternoon Hans Kjeldsen (Aarhus) gave a very nice seminar about Kepler. He showed that they can use helioseismology to determine the fraction of hydrogen burning that has completed inside a star; that is, as a clock! He showed nice results on exoplanets too, including surprising albedo measurements and a demonstration that multi-planet systems draw their planets from a different distribution than single-planet systems. That's nice. He said that in exchange for a mission extension, the Kepler team is giving away all the data with no proprietary period, starting soon. That might have a big impact on my activity in the next year!