The octatetraynylide ion has been detected toward the dark cloud TMC-1 in four rotational transitions between 24 and 16 mm:
S. Brünken, H. Gupta, C. A. Gottlieb, M. C. McCarthy, and P. Thaddeus,
Detection of the Carbon Chain Negative Ion C<sub>8</sub>H<sup>–</sup> in TMC-1
Astrophys. J. 664, L43–L46 (2007).
At almost the same time it had been detected in observations toward the carbon rich star IRC +10216 in 5 rotational transitions occuring at 12 and around 7 mm:
A. J. Remijan, J. M. Hollis, F. J. Lovas, M. A. Cordiner, T. J. Millar, A. J. Markwick-Kemper, and P. R. Jewell,
Detection of C<sub>8</sub>H<sup>–</sup> and Comparison with C<sub>8</sub>H toward IRC +10216
Astrophys. J. 664, L47–L50 (2007).
Contributor(s): H. S. P. Müller; 7, 2007