The author of Astronomica is neither quoted nor mentioned by any ancient writer. Even his name is uncertain, but it was probably Marcus Manilius; in the earlier books the author is anonymous, the later give Manilius, Manlius, Mallius. The poem itself implies that the writer lived under Augustus or Tiberius, and that he was a citizen of and resident in Rome. According to the early 18th century classicist Richard Bentley, he was an Asiatic Greek; according to the 19th-century classicist Fridericus Jacob, an African. His work is one of great learning; he had studied his subject in the best writers, and generally represents the most advanced views of the ancients on astronomy. Manilius frequently imitates Lucretius, whom he resembles in earnestness and originality and in the power of enlivening the dry bones of his subject. Although his diction presents some peculiarities, the style is metrically correct. The astrological systems of houses, linking human affairs with the circuit of the zodiac, have evolved over the centuries, but they make their first appearance in Astronomicon. The earliest datable survivinghoroscope that uses houses in its interpretation is slightly earlier, c. 20 BC. Claudius Ptolemy almost completely ignored houses in his astrological text, Tetrabiblos. The work is also known for being the subject of the most salient of A. E. Housman's scholarly endeavours; his annotated edition he considered his magnum opus, and when at last the final volume was published 27 years after the first in 1930, he remarked he would now "do nothingforever and ever." Housman nonetheless also thought that it was an almost absurdly obscure pursuit; to an American correspondent he wrote, "I do not send you a copy, as it would shock you very much; it is so dull that few professed scholars can read it, probably not one in the whole United States." It remains a source of bafflement to many that Housman should have elected to abandon his obsession for a poet as consummate as Propertius – which indeed cost him his degree, so consuming was the passion – in favour of Manilius. For example, the critic Edmund Wilson pondered the countless hours Housman devoted to Manilius and concluded, "Certainly it is the spectacle of a mind of remarkable penetration and vigor, of uncommon sensibility and intensity, condemning itself to duties which prevent it from rising to its full height."
