  The formation of globular clusters (GC) with their multiple stellar
populations remains a puzzling, unsolved problem in astrophysics. One way to
gather critical insight consists in finding sizable numbers of GC progenitors
(GCP) while still near the peak of their star formation phase, at a lookback
time corresponding to GC ages (~12.5 Gyr, or z ~ 5). This opportunity is
quantitatively explored, calculating how many GCPs could be detected by deep
imaging in the optical, near-IR and mid-IR bands. For concreteness, for the
imaging camera performances those of NIRCam on board of JWST are adopted. The
number of GCPs that could be detected scales linearly with their mass, i.e., on
how much more massive GCPs were compared to their GC progeny, and perspectives
look promising. Besides providing direct evidence on GC formation, the
detection of GCPs, their clustering, with or without a central galaxy already
in place, would shed light on the relative timing of GC formation and galaxy
growth and assembly. All this, may be the result of dedicated observations as
well as a side benefit of deep imaging meant to search for the agents of cosmic
reionization.

Astrophysics of Galaxies