  We present the first detection of interstellar acetone [(CH3)2CO] toward the
high mass star forming region Orion-KL and the first detection of vibrationally
excited (CH3)2CO in the ISM. Using the BIMA Array, 28 emission features that
can be assigned to 54 acetone transitions were detected. Furthermore, 37 of
these transitions have not been previously observed in the ISM. The
observations also show that the acetone emission is concentrated toward the hot
core region of Orion-KL, contrary to the distribution of other large oxygen
bearing molecules. From our rotational-temperature diagram we find a beam
averaged (CH3)2CO column density of (2.0(0.3)-8.0(1.2))x10^16 cm^-2 and a
rotational temperature of 176(48)-194(66) K.
