1995A&A...299..583C

We report the detection of molecular gas emission associated with the Keyhole nebula located near Eta Carinae. A detailed map of ¹²CO(2-1) is presented covering a field of 8x7arcmin². In a few directions other molecular lines were observed. The distribution of the molecular gas is very inhomogeneous, breaking up into at least nine clumps most of them well separated both in space and in velocity. Their typical size is a few tenths of a parsec with linewidths in the range 2-4km/s and masses of ∼10M_☉. We present evidence suggesting that the dense clumps are unbound and supported by the external pressure of the surrounding ionized gas. The dynamics of the molecular gas are highly perturbed: the clumps separation, projected in the plane of the sky, is of less than a parsec with velocity differences of up to 20km/s. Such a velocity dispersion, which is comparable with that measured in the ionized gas, is likely to be a result of the interaction between the strong stellar winds of Eta Carinae and the surrounding gas.