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