Tycho Magnetic Anomaly TMA-1

In Arthur C. Clarke's Space Odyssey, monoliths are machines built by an unseen extraterrestrial species. In the series of novels (and the films based on these), three monoliths are discovered in the solar system by humans. (It is also revealed that thousands of others, if not more, exist elsewhere in the solar system.) The response of the characters to their discovery drives the plot of the series. It also influences the fictional history of the series, particularly by encouraging humankind to progress with technological development and space travel.

The first monolith appears at the beginning of the story, set in prehistoric times. It is discovered by a group of hominids and somehow triggers a considerable shift in evolution, starting with the ability to use tools and weaponry.

The extraterrestrial species that built the monoliths is never described in much detail, but some knowledge of its existence is given to Dave Bowman after he is transported by the stargate to the "cosmic zoo", as detailed in the novels 2001: A Space Odyssey and 2010: Odyssey Two. The existence of this species is only hypothesized by the rest of humanity, but it is obvious because the monolith was immediately identified as an artifact of non-human origin.

The extraterrestrial species that built the monoliths developed intergalactic travel millions or perhaps billions of years before the present time. In the novels, Clarke refers to them as the "Firstborn" (not to be confused with the identically-named race in Arthur C. Clarke's and Stephen Baxter's Time Odyssey series) since they were quite possibly the first sapient species to possess a significant capability of interstellar travel. Members of this species explored the universe in the search of knowledge, and especially knowledge about other intelligent species.

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