  Juno Mission to Jupiter has found closely-packed cyclones at the planet's two
poles. The observation that these cyclones coexist in very confined space, with
outer rims almost touching each other but without merging, poses a big puzzle.
In this work, we present numerical calculations showing that convectively
sustained, closely-packed cyclones can form and survive without merging for a
very long time in polar region of a deep rotating convection zone (for
thousands of planetary rotation periods). Through an idealized application of
the inertial stability criterion for axisymmetric circulations, it is found
that the large Coriolis parameter near the pole plays a crucial role in
allowing the cyclones to be packed closely.
