Unbound

We all know the Silver Surfer was herald to the mighty Galactus. The ancient celestial giant fed off planets, consuming them whole, absorbing every ounce of its energetic matter, fulfilling his demanding hunger which kept him in flight through the cosmos. Silver Surfer was the obedient guide to locate the next lineup of planets to be fed upon.
This artistic impression of Galactus is a variant I often considered to be an improvement from his traditional outfit. An outfit that contains similarities of two very old cultures. Not only that, I also developed a scenario regarding an earlier close encounter we may have had with this threat to Earth.
The ancient Egyptian and Mayan civilizations both endured mysterious happenings and questionable endings. They encountered events that led to many myths and beliefs, parallel to some advancements in their knowledge. Thus, it is my comical belief that Silver Surfer arrived to Earth at this time and gave huge influence to their cultures. A river of mercury has been found within Mayan pyramids, and Egyptian god relative to mercury, Thoth. These attributes are their foundation to knowledge. As well as both being skilled in astronomy, which the Surfer no doubt had a hand in.
(as a side note: some of the Silver Surfer storylines go into the level of influence he may have had with primitive beings on other planets, and to what measure they evolved. Sometimes ending in catastrophe.)
The Surfer was also compelled to warning them of the approaching doom, of whom he served. It is my belief he may have had some compassion to life on this planet, and projected to the unequipped societies everything about the incoming threat, including Galactus' appearance, something rarely seen or known.
It is not known what took place upon the celestial's arrival, however I suspect the creation of many of the pyramids around the world, along with sacred elements within Mother Earth's resources combined may have thwarted the attack, possibly metaphysically. Nonetheless, the priests and chiefs and much of their ancient culture were impacted by the great force and power that nearly ended life on this planet.
Evading this certain demise has only been known to take place once before, with Silver Surfer and his own planet.