Vol. 536
In section 7. Stellar structure and evolution

An incisive look at the symbiotic star SS Leporis. Milli-arcsecond imaging with PIONIER/VLTI

The binary system 17 Leporis (also known as SS Lep) has a has a long history of being ''a mystery''. It has many features in common with symbiotic star wide binary systems but with the hot companion being a main-sequence star instead of a degenerate companion. It has also been identified as an Ae/Be star, perhaps even a pre-main sequence binary. The system resembles a mass-exchanging close binary with Roche lobe overflow, the usual Algol-type binary, but it is more likely wind accretion near the Roche surface. The authors, using the most advanced interferometric observations attempted to date of this or related systems, have succeeded in separating the binary from an extended circumstellar envelope that also yields masses and a definitive orbit that rules out anything but an evolved system scenario. This star is an extreme in the Algol class and likely an example of the stage that all such systems pass through. The paper is a landmark in stellar interferometry.