  Picture yourself in the wave zone of a gravitational scattering event of two
massive, spinning compact bodies (black holes, neutron stars or stars). We show
that this system of genuine astrophysical interest enjoys a hidden
$\mathcal{N}=2$ supersymmetry, at least to the order of spin-squared
(quadrupole) interactions in arbitrary $D$ spacetime dimensions. Using the
${\mathcal N}=2$ supersymmetric worldline action, augmented by finite-size
corrections for the non-Kerr black hole case, we build a quadratic-in-spin
extension to the worldline quantum field theory (WQFT) formalism introduced in
our previous work, and calculate the two bodies' deflection and spin kick to
sub-leading order in the post-Minkowskian expansion in Newton's constant $G$.
For spins aligned to the normal vector of the scattering plane we also obtain
the scattering angle. All $D$-dimensional observables are derived from an
eikonal phase given as the free energy of the WQFT, that is invariant under the
$\mathcal{N}=2$ supersymmetry transformations.
