KH 15D on YouTube

KH 15D illustration

The unique behavior of this “winking star” was discovered in 1995 with the 24 inch (Perkin) telescope at Van Vleck. We continue to follow it at Wesleyan but most data now comes from the SMARTS telescope at Cerro Tololo Interamerican Observatory in Chile. It has been fascinating to see the light curve evolve over the years as precession of the disk has caused various parts of the orbits of the stars to be covered or revealed.

Just recently the star has brightened again, unexpectedly, and it appears that the previously unseen binary component is now peeking out the bottom of the disk. This phase is not shown in the current animation because it was created before we knew this was going to happen.

An interesting aspect of the star is that when it forms a planetary system (IF it forms one!) the planets will probably transit the stars, just like several systems recently discovered by the Kepler satellite, including Kepler 16 (sometimes referred to as Tatooine, after the mythical Star Wars planet orbiting a binary star). KH 15D may, therefore, be described as a proto-Tatooine.

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