He was a philosopher under the influence of the Stoa. For some time, he lived in Athens, then at the court of Antigonos of Macedonia, then at the court of Antiochos I. of Syria.
In his astronomical poem, Phainomaina or Phainomena [Heavenly Phenomena, or Appearances], he describes the sky and mentions, among others, the Praesepe Star Cluster (M44) as "A little Mist," or faint nebula in Cancer (see his remark). This is the first known preserved description of this cluster in ancient sources. Aratos also mentions the star clusters of the Pleiades (M45) and the Hyades in Taurus, as clusters of stars.
Aratos is commemorated with the naming of Moon crater Aratus, situated at 23.6d N, 4.5d W, of 24 km diameter, in 1935 by IAU.
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