The vast majority of individuals are completely unaware of what they are looking at. I’m not sure what kind of extraterrestrial we’re dealing with here, but it could be Greys from the Zeta star systems. This is the antigravity force field in action; you can hear the electric field motor rotating.
The Grey applied a voltage DC charge to tubular capacitors above the rotating thorns field when the field’s rpm reached a specific level.
The faster the take-off, the higher the voltage! A brief burst of charging plasma can be seen during takeoff. Charged plasma ionized air is suspended in an antigravity force field. These extraordinary ships can reach speeds of up to 30,000 miles per hour in our atmosphere.
The greys may have been aware that they had been observed and were unsure how humans, as primitive beings, would react.
If we believe that Earth is the only world in the Universe containing life, we are delusory. We are not alone, and different alien species are currently live among us. Others want to take our place, while others help us transition to stage 2 civilization.