Eight controversial clusters were studied with the help of the Hipparcos and ACT catalogues. We confirm the reality of Collinder 135 and NGC 2451 A. It seems possible that star clusters are present in the areas of NGC 2451 B, Collinder 132 and Roslund 5. Collinder 399, Upgren 1, NGC 1252 and Melotte 227 are found to be chance alignments of stars.
© European Southern Observatory (ESO) 1998
Online publication: November 9, 1998