ハーバード・スミソニアン天体物理学センター
Soker was a postdoctoral researcher at the University of Virginia from 1986 to 1989, and continued for a second post-doctoral degree at the Harvard–Smithsonian Center for Astrophysics (19891992). During that time he developed models for cooling flows in galaxy clusters, and started to work in the field of planetary nebulae.