Due to its youth, proximity and richness, the Orion nebula cloud (ONC) is an ideal testbed to obtain a comprehensive view on the initial mass function (IMF) down to the planetary mass regime. Using the HAWK-I camera at the VLT, we have obtained an unprecedented deep and wide near-infrared JHK mosaic of the ONC (90 per cent completeness at K ~19.0mag, 22x28 arcmin^2^). Applying the most recent isochrones and accounting for the contamination of background stars and galaxies, we find that ONC's IMF is bimodal with distinct peaks at about 0.25 and 0.025M_{sun} separated by a pronounced dip at the hydrogen burning limit (0.08M{sun}), with a depth of about a factor of 2-3 below the log-normal distribution. Apart from ~920 low-mass stars (M0.005M{sun}, hence about 10 times more substellar candidates than known before. The substellar IMF peak at 0.025M{sun}_ could be caused by brown dwarfs and isolated planetary mass objects which have been ejected from multiple systems during the early star formation process or from circumstellar discs.

Cone search capability for table J/MNRAS/461/1734/tablea1 (Catalogue of the HAWK-I sources)