Greg Orme has been researching possible Martian artifacts since 1994. He was the discoverer of the Crowned Face and other possible artifacts in the King's Valley. He wrote a book on this subject, "Why we must go to Mars: The King's Valley" available for free download on his website-- ultor.org. He co-authored a peer reviewed paper on the Martian Spiders in the Journal of the British Interplanetary Society, discovered the first spider image M0804688, and introduced them to Arthur C. Clarke. He has three peer-reviewed papers in the recent Mars issue of the Journal for Space Exploration