The first interstellar feature that could be assigned to tricarbon monoxide (C₃O) was reported in 1984 by Matthews et al. using their own laboratory data published the previous year. A second report in 1985 increased the number of observed lines to four, all in the Taurus Molecular Cloud (TMC-1). An extensive survey from 2004 by Kaifu et al. confirmed the detection of C₃O in TMC-1 and added another line. The species has also been found in the circumstellar cloud toward IRC +10216 by Tenenbaum et al. and toward the low-mass protostar Elias 18 by Palumbo et al. Prof. Ronald Brown discussed his work with tricarbon monoxide in a 2008 interview.