IC 2602

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IC 2602, generally known as the Southern Pleiades or Theta Carinae Cluster, is an open cluster in the constellation Carina that was discovered by Abbe Lacaille in 1751 from South Africa. Easily seen with the naked eye, this cluster is one of the closest to us, whose distance is about 167.7 parsecs (547 light-years) away from Earth.

The Southern Pleiades (IC 2602) has a total apparent magnitude of 1.9, which is 70% fainter than the Taurean Pleiades, and contains about seventy-four stars. It is the third-brightest open cluster in the sky, following the Hyades. Like its northern counterpart, the Southern Pleiades spans a sizeable area of sky, approximately 50 arcminutes, so it is best viewed with large binoculars or telescope with a wide-angle eyepiece.

Theta Carinae is the brightest star within the open cluster, being third-magnitude with the apparent photometric magnitude of +2.74. All the other stars within the cluster are of the fifth magnitude and fainter. The cluster is thought to have the same age as the open cluster IC 2391, which has a lithium depletion boundary age of 50 million years old, though the accepted true age is 13.7 million years. IC 2602 is also likely part of the Lower Scorpius-Centaurus OB Association.