disappear from the Solar System. Tycho Magnetic Anomaly-0 In the year 2513, the first Monolith to be encountered by humankind's prehistoric evolutionary predecessors (the ones featured in the first novel) was found in Olduvai Gorge, buried in ancient rock, and was retroactively dubbed "TMA-0". Other Monoliths Other than the Monoliths bearing TMA labels, there are many other Monoliths that are seen in the series. In two instances, millions of Monoliths are generated for a limited time purpose. In the first, in 2010: Odyssey Two, millions of Monoliths are generated to transform Jupiter into a star, subsequently named Lucifer. In the second, in 3001: The Final Odyssey, millions of monoliths are generated to block both the Earth and human-settled Ganymede from their primary star in an attempt to destroy the humans. Other specific monoliths are described below. The Great Wall A large Monolith is found resting on its side on Europa in the 2061 novel. It is nicknamed the Great Wall after the Great Wall of China due to its horizontal orientation. It is believed to be watching over the Europans in a manner similar to what TMA-0 did on Earth in the first book. The 2061 novel implies that this Monolith is TMA-2 from the previous novel, but the characters never refer to it as TMA-2 or "Big Brother." It is described as being the same size as TMA-2 and is the home to the digitized minds of Bowman and HAL just as TMA-2 was at the end of the last novel. However, the 3001 novel changes the description of the Great Wall to be 20 kilometers long, so it is unclear whether this monolith is the same as TMA-2 or not. In 2061, Bowman and HAL describe how it was knocked on its side and possibly damaged by the impact of Mount Zeus, a vast diamond shard from Jupiter's core that struck Europa's surface some time following Jupiter's transformation. But in 3001, the monolith on its side is described as having a purpose to protect the evolving Europans. (Arthur C. Clarke admitted to changing some concepts each time he wrote another sequel novel so it is not possible to fully reconcile TMA-2 and The Great Wall.) Minilith A small Monolith appears before Heywood Floyd in 2061 on board the Galaxy spacecraft. He nicknames it "Minilith" for its small size compared to other observed Monoliths. At the end of the