Valentin Ivanov (astronomer)

Valentin D. Ivanov (Bulgarian: Валентин Д. Иванов) is a Bulgarian astronomer working in the European Southern Observatory, mainly at the Paranal site. Among his primary research areas are the dynamics of star clusters, formation of stars, brown dwarfs, and exoplanets around such objects.

Valentin Ivanov and Ray Jayawardhana are two of the pioneers of the investigation of the planemos. They discovered the extremely low low mass binary Oph 162225-240515 whose components were thought for a while to be planetary mass objects (a.k.a. planemos). This discovery came just before the debate about the 2006 planet definition, and posed the problem about the distinction between planets and brown dwarfs.