"It is a fireball lightning... first time I have seen one. It's moving away... lost it. Where is it? There... I wonder if it'll blow off soon..."
Many viewers complained that the video was filmed in portrait (vertical position) rather than in landscape (horizontal position). Others complained it was shaky.
The complaints forced a woman, who identified herself as Tregubov's daughter (Jenny T.), to offer an apology.
"Everyone is commenting on my dad's video taking skills.. I'm terribly sorry he chose to look at the actual event instead of at the camera."
"Ball lightning? Tell me how it is able to fly across the sky like that!"
Most ball lighting range from pea-size to a few meters across. But the bright luminous sphere shown in the video appeared to be a massive orb, several meters across, based on a reasonable estimate of the distance from the fence.
Yet other commenters noted that most ball lightning dissipate very quickly, usually explosively. But the orb shown in the video was long-lived. It glided slowly across the large field and until it passed out of sight it remained intact.
However, some viewers agreed with Tregubov that it was ball lightning.
"It's just ball lightning," a viewer said. "I've seen a few of those in the neighboring Altai region in the 90s."
But the viewer agreed that ball lightning tends to dissipate quickly,unlike the mysterious object shown in the video.
"They always seem to dissipate relatively quickly," he said.
Ball lightning phenomenon is not well understood by science but it is considered an electrical phenomenon often associated with thunderstorms. It usually appears briefly as a small luminous spherical object a few inches or meters across, but lasts longer than the typical lightning flash.
Ball lightings often disintegrate by exploding.
[Image via Shutterstock]