Do you know what an OOPART is? Is it some unmentionable alien genitalia ("eew-parts!")? Maybe shorthand for the part that a tuba plays in Bavarian music (oom-pah-pah, oom-pah-pah)? No. OOPART is an acronym for Out of Place Artifact, evidence of ancient technology that existed long before human biological or technological evolution says it should exist. While OOPARTs are largely discredited by mainstream science, they can play a valuable role in coming up with a plot for your next sci-fi novel or thriller. In fact, OOPARTs can be found in many best-selling novels. In Lincoln Child's novel, Deep Storm, a deeply submerged OOPART that may be evidence of Atlantis plays a central role in the plot. In his Sigma Force thriller, The Devil's Colony, James Rollins focused the plot around two sets of OOPARTS found in a cave – a set of prehistoric mummies and a set of gold plates etched with an unfathomable cipher. Perhaps the most famous OOPARTs found in fiction are the twin monoliths discovered at the beginning of 2001: A Space Odyssey. In my sci-fi novella, Eden, an American Army patrol investigating recently uncovered ancient ruins discovers an OOPART in the form of a stone sarcophagus. Stone sarcophagi are not unusual, but this one is manufactured in ways that the ancients should never have been able to produce. Eden, of course, is fiction but ancient, finely honed stone masonry is not. From the pyramids of Giza to the massive walls of Bolivia's Puma Punku, the stonework of early Egyptians and the pre-Incan Andeans called Tiwanakus is so finely worked that stonemasons today say it exceeds their capabilities with all their modern tools. Like the stone sarcophagus found by Captain Cadman and his soldiers in Eden, the stonework found at Puma Punku is said to have such microscopic tolerance that you can't insert the blade of a sharpened knife into the seams between stones. Mainstream scientists, however, disagree that such stonework was beyond the means of the early Egyptians and Andeans, and for all I know they are probably right. However, there remain many more OOPARTs that might inspire a writer's imagination.Miners in South Africa reportedly have been finding hundreds of metallic spheres that appear to be manmade. Yet the spheres are found in sedimentation dated back to 2.8 billion years ago. In 1991, evidence of what appear to be manmade nanostructures was found in sediment along three Russian rivers. The structures – coils, spirals, and other shapes – ranged in size from 1.18 inch to 1/10,000 of an inch, and were found at a soil depth of 10 to 40 feet in strata dated back to between 20,000 to 300,000 years. Doubters say the objects are either debris from nearby Russian space launches or naturally occurring structures. Another mysterious OOPART is the Chimu Telephone, dated back 1,200 to 1,400 years. The Chimu, ancient Peruvians, linked two gourds with a cord to form a primitive sound-powered phone similar to the old string-and-tin can phones children used to play with before they started using smart phones. Though definitely not high-tech, the Chimu Telephone demonstrates knowledge of sound propagation and transmission not normally credited to such ancient people. Perhaps the best-known OOPART is the Antikythera mechanism, discovered in the early 1900s in a shipwreck off the Greek island of Antikythera and dated back to dated back to at least 100 BCE and maybe as far back as 205 BCE. The device is a complex meshing of bronze gears that can predict astronomical positions and eclipses, and is considered the oldest example of an analog, or mechanical, computer. While the ancient Greeks certainly had the knowledge of advanced mathematics to create the device, they were not known to have such an advanced knowledge of gears and mechanics. OOPARTs like these have generated a great deal of conflict (something every good story needs) between mainstream scientists and those involved in what might be called crypto-science. In Eden, I personify this conflict in the character of Captain Cadman. Cadman – a part-time National Guard soldier who, in civilian life, is an archeologist – finds himself torn by what he knows as a scientist and the things he finds inside the ancient ruins. He finally has to concede that much of what is considered scientific fact is simply scientific consensus. A collective of scientists buys into a school of thought and it becomes fact, he explains. Yet beliefs once thought to be scientific fact, he admits, are often disproved decades later. Whether OOPARTS are out of place technology or just the products of bad science and overactive imaginations, they remain an inspiration for writers, especially those of us who write science fiction or archaeological thrillers.