  All planets and stars rotate. All gas planets in our solar system, the Sun,
and many stars show a pattern of east- or westward mean flows. This phenomenon
is known as differential rotation in the stellar and as zonal jets in the
planetary context. Observations, laboratory experiments and simulations show
that the zonal flow kinetic energy scales like $\ell^{-5}$, where $\ell$ is the
spherical harmonic degree (which is effectively a latitudinal wave number).
Here, we analyze observation of the Sun, as well as simulations of the dynamics
in Saturn and in the outer atmosphere of an ultra-hot Jupiter. While these
systems are very different, they all develop strong zonal winds that obey the
$\ell^{-5}$ scaling. Our results strongly suggest that there is a simple common
mechanism that shapes zonal mean flows in planets and stars independent of the
flow driving.
