1:40 PM PT -- Sources with direct knowledge tell TMZ ... these balls do not belong to Tommy Lee.

We're told Tommy Lee had, in fact, posted this video on his socials -- but only after it was sent to him ... at which point he posted it, but deleted it a short time later. In other words, these testes aren't Tommy's ... despite the rumors that are going around.

That's one fella ruled out!

That's NOT the moon blocking the light -- one Mexican TV station's solar eclipse coverage Monday was totally nuts, as in the pair of testicles that somehow ended up on the screen ... and they might be famous!

Check it out ... news anchors for Mexico's RCG Media were commenting just as the eclipse entered totality, but things really got interesting when they cut to a different angle of a bright light ... presumably the sun.

Seconds later, the testes dipped into frame, blocking the light ... and giving audiences a brief, but very up-close look at someone's family jewels. You could see the visible shock on the faces of 2 of the anchors on set.

Though RCG Media is likely not laughing over the on-air hiccup, the Internet has gotten a kick out of the now viral mooning, joking the flashing did more damage to their eyesight than the eclipse.

As for how the testicles ended up on the broadcast??? RCG Media reportedly asked viewers to send in personal eclipse footage ... which, in hindsight, was a very risky idea. There's even a theory floating around social media that the balls in question were attached to Tommy Lee!

The Motley Crue drummer reportedly posted and deleted an eerily similar eclipse re-creation with his testicles -- which might have, somehow, leaked into the RCG control room.

Thankfully, the viral flashing didn't eclipse the big day, with millions stepping outside to experience the rare occurrence. Celebrities like Patrick Mahomes, Nina Dobrev and Jessica Biel all threw on eclipse glasses to watch the total solar eclipse pass over the United States.

The next total solar eclipse in the U.S. isn't until 2044. FWIW, Tommy would be in his early 80s ... so, they'd be hanging REALLY low by then!