  We introduce a new purely bosonic, $\frac{1}{6}$ BPS Wilson loop for ABJM
theory on $S^3$ that couples scalar fields to a latitude at an angle $\theta$
on $S^2\in\mathbb{C}P^3$. Through localization of this operator, we relate the
expansion of the cusp anomalous dimension at small cusp angles to the
logarithmic derivative of the ABJM Wilson loop. This defines,
non-perturbatively in the 't Hooft coupling, the bremsstrahlung function
$B(\lambda)$ describing in three dimensions the soft radiation of a $W$-boson
undergoing a sudden change in trajectory. We compare our results for
$B(\lambda)$ to the known weak/strong coupling expansions of the function
$h(\lambda)$ that enters integrability. At weak coupling we precisely match the
previously known two-loop result. At strong coupling we find agreement at
leading order in $\sqrt{\lambda}$, but a mismatch of the constant coefficient.
We comment on the striking similarity that we observe between these two, in
principle, unrelated functions.
