AURA/ESO group during CTIO's early days

AURA-ESO group on horseback at the saddle between Cerro Tololo and Cerro Morado. Left to right: Ch. Fehrenbach, O. Heckmann, Sr. Marchetti, J.H. Oort, N.U. Mayall, F.K. Edmondson and A.B. Muller. June 10th 1963. From `AURA and its US National Observatories' by Frank Edmondson, Cambridge University Press, 1997.