Antennae
 

Underwater, by the craven warmongers in submarines,
and beyond the atmosphere in outer space they
cannot be aerials (formerly aerial wires) because
there isn't any air.

Therefore, they must be antennae.

Antennae
 

On Thu, 27 Jul 2017 11:38:32 +0100, Gareth's Downstairs Computer
wrote:

Underwater, by the craven warmongers in submarines,
and beyond the atmosphere in outer space they
cannot be aerials (formerly aerial wires) because
there isn't any air.

'Aerial' also means 'in an elevated position' which is almost
certainly why the noun was coined. The presence or absence of air is
irrelevant.

Therefore, they must be antennae.

False dichotomy.