We report new VLT/NACO imaging observations of the young, nearby brown dwarf
2MASSW J1207334-393254 and its suggested planetary mass companion (2M1207 b).
Three epochs of VLT/NACO measurements obtained over nearly one year show that
the planetary mass companion candidate shares the same proper motion and, with
a high confidence level, is not a stationary background object. This result
confirms the status of 2M1207 b as of planetary mass (5 times the mass of
Jupiter) and the first image of a planetary mass companion in a different
system than our own. This discovery offers new perspectives for our
understanding of chemical and physical properties of planetary mass objects as
well as their mechanisms of formation.Comment: 4 pages, 2 figures. accepted in Astronomy & Astrophysic