  Collisional families offer a unique window into the interior composition of
asteroid populations. Previous dynamical studies of the Jupiter Trojans have
uncovered a handful of potential collisional families, two of which have been
subsequently confirmed through spectral characterization. In this paper, we
present new multiband photometric observations of the proposed Ennomos family
and derive precise $g-i$ colors of 75 candidate family members. While the
majority of the targets have visible colors that are indistinguishable from
background objects, we identify 13 objects with closely grouped dynamical
properties that have significantly bluer colors. We determine that the true
Ennomos collisional family is tightly confined to $a'_{p} > 5.29$ au and $0.45
< \sin{i_{p}} < 0.47$, and the majority of its confirmed members have
near-solar spectral slopes, including some of the bluest objects hitherto
discovered in the Trojan population. The property of distinctly neutral colors
that is shared by both the Ennomos family and the previously characterized
Eurybates family indicates that the spectral properties of freshly exposed
surfaces in the Jupiter region are markedly different than the surfaces of
uncollided Trojans. This implies that the processes of ice sublimation and
space weathering at 5.2 au yield a distinct regolith chemistry from the
primordial environment within which the Trojans were initially accreted. It
also suggests that the Trojans were emplaced in their present-day location from
elsewhere sometime after the initial population formed, which is a key
prediction of recent dynamical instability models of solar system evolution.
