IC 2391

Open Cluster IC 2391 (= Lacaille II.5), type 'c', in Vela

The Omicron Velorum Cluster

Right Ascension 08 : 40.2 (h : m)
Declination -53 : 04 (deg : m)
Distance 0.58 (kly)
Visual Brightness 2.5 (mag)
Apparent Dimension 50 (arc min)

Discovered by Al Sufi before 964 AD.

This bright southern cluster was first described by the old Persian astronomer Al Sufi about 964 AD. Nicholas Louis de Lacaille found it independently on February 11, 1752, and cataloged it as Lac II.5.

Its brightest star is of apparent magnitude 3.63, its hottest of spectral type B3, and its age is given as 36 million years in the Sky Catalog 2000, which also gives its Trumpler class: II,3,p. It consists of about 30 stars.

Our image was obtained by David Malin of the Australian Astronomical Observatory and is copyrighted; it may be used for private purpose only. For any other kind of use, including internet mirroring and storing on CD-ROM, please contact the Photo Permissions Department (photo at aaoepp.aao.gov.au) of the Australian Astronomical Observatory.

  • More images by David Malin

    In John Caldwell's observing list. In the Astronomical League's Southern Sky Binocular Club list. Caldwell 85 in Patrick Moore's list.

  • Jean-Claude Mermilliod's WEBDA cluster page for IC 2391
  • SIMBAD Data of IC 2391
  • Publications on IC 2391 (NASA ADS)
  • Observing Reports for IC 2391 (IAAC Netastrocatalog)
  • NGC Online data for IC 2391

    Hartmut Frommert
    Christine Kronberg

    [SEDS] [MAA] [Home] [Non-Messier Indexes]

    Last Modification: March 29, 1998