>Quiet and exhaust free.

Which is fairly impressive at the reported velocity of 2400mph.

What if it’s a hack? Get the enemy to think they’re seeing UFOs and maybe they’ll slip up on “mundane” foreign planes? Not a huge effect but it might only need to work once.

But the news of water ice on titan - and a huge band of it - makes me wonder if life hasn’t spawned twice (at least) in the solar system.

One thought I had was a plasma ball being generated by focusing high UV from a satellite. That fits some of the supposed behaviour.

While maybe not exactly impossible that would require some insane UV laser power from a satellite.

Might not be space, the water disturbances could be projectors submerging.

Well a nuclear sub might have the power needed. Still insane though. :) Probably you would need several lasers too, intersecting where you want to have the plasma ball.

Thinking about the current efficiency of big lasers, a sub also has the benefit of being able to dump heat fast.

FLIR shows a very low heat signature, though. Plasma is hot (and usually doesn't maneuver.)

The femtosecond mini plasma holograms are cold enough (on average) to touch - Fairy Lights in Femtoseconds: Aerial and Volumetric Graphics Rendered by Focused Femtosecond Laser Combined with Computational Holographic Fields - https://arxiv.org/abs/1506.06668

Traveling 2400 MPH?