Ancient Aliens became a popular image macro meme from 2010-2012, spreading particularly through Reddit and image boards. The format featured Tsoukalos making his distinctive gesture with text typically stating 'I'm not saying it was aliens, but... aliens.' The meme was used to attribute improbable or ridiculous explanations to everyday situations, making light of the show's conspiratorial approach.

The meme thrived on the absurdity of the 'Ancient Aliens' premise, allowing people to humorously 'explain' anything through alien intervention. It became a running joke in online culture, appearing in countless variations. The show's popularity helped maintain the meme's visibility, as new viewers discovered both the show and the meme at the same time.

Unlike many image macros that peaked and died, Ancient Aliens has maintained some cultural relevance. The meme is still used occasionally, particularly when discussing absurd explanations or conspiracy theories. Giorgio A. Tsoukalos has acknowledged the meme's existence and has demonstrated good humor about his accidental cultural icon status.