The search engine said on its official blog Monday the images were inspired by Wells' novel "The War of the Worlds" and were posted to the Web site to mark the 143rd anniversary of the author's birth in Bromley, England, the Daily Mail reported Monday.
The company said the UFO and crop circle logo was the last part in a series of clues hidden within the Google main page logo starting Sept. 5.
"Now, we're finally acknowledging the reason for the doodles with an official nod to Herbert George, who would be 143 years old today," the official Google blog read Monday. "The invasion of the logo by alien crafts and pods makes our series complete, but you'll have to read the book to find out how Wells' story really ends."
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