Dan Foreman-Mackey (UW) appeared for a few days in New York City. I had various conversations with him, including one in which I sanity-checked my data-driven model for radial velocities. He was suspicious that I can take the first-order (linear) approximation on the velocities. I said that they are a thousandth of a pixel! He still was suspicious. I also discussed with him the point of—and the mathematical basis underlying—the project we have with Adrian Price-Whelan (Princeton) on inferring companion orbits from stellar radial-velocity data. He agrees with me that we have a point in doing this project despite its unbelievably limited scope! Remotely, I worked a bit more on the wide-separation binaries in Gaia DR1 with Price-Whelan.