Letter to the Editor

Giant planet companion to 2MASSW J1207334-393254

¹ European Southern Observatory, Casilla 19001, Santiago 19, Chile e-mail: gchauvin@eso.org
² Laboratoire d'Astrophysique, Observatoire de Grenoble, 414 rue de la piscine, Saint-Martin d'Hères, France
³ Department of Physics & Astronomy and Center for Astrobiology, University of California, Los Angeles, Box 951562, CA 90095-1562, USA
⁴ Laboratoire d'Astrophysique, Observatoire Midi-Pyrénées, Tarbes, France
⁵ Spitzer Science Center, Infrared Processing and Analysis Center, MS 220-6, Pasadena, CA 91125, USA

Received: 5 April 2005
Accepted: 28 April 2005

Abstract

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.