F. Combes, M. Gerin, A. Wooten, G. Wlodarczak, F. Clausset, and P. J. Encrenaz,
Acetone in Interstellar Space
Astron. Astrophys. 180, L13–L16 (1987);
detected propanone, aka acetone, for the first time in the interstellar medium. Observations were made with the IRAM 30m, Greenbank 43m, and Kitt Peak 12m telescopes toward Sgr B2. The column density of 5 × 10¹³ cm^–2 were much higher than values predicted by models of that time. Therefore, this detection was not accepted by many in the community for a long time.

15 years later, this detection was confirmed:
L. E. Snyder, F. J. Lovas, D. M. Mehringer, N. Y. Miao, Y.-J. Kuan, J. M. Hollis, and P. R. Jewell,
Confirmation of Interstellar Acetone
Astrophys. J. 578, 245–255 (2002).

More recently, propanone was detected towards the high-mass star-forming region Orion KL:
D. N. Friedel, L. E. Snyder, A. J. Remijan, and B. E. Turner,
Detection of Interstellar Acetone toward the Orion-KL Hot Core
Astrophys. J. 632, L95–L98 (2005).
Besides a very large number of transitions in its ground vibrational state, a few lines of the first excited torsional state were reported. Even though the number of vibrationally excited lines is small, the consistent global modeling ensures this aspect of the detection.

J. M. Lykke, A. Coutens, J. K. Jørgensen, M. H. D. van der Wiel, R. T. Garrod, H. S. P. Müller, P. Bjerkeli, T. L. Bourke, H. Calcutt, M. N. Drozdovskaya, C. Favre, E. C. Fayolle, S. K. Jacobsen, K. I. Öberg, M. V. Persson, E. F. van Dishoeck, and S. F. Wampfler
reported on
The ALMA-PILS Survey: First Detections of Ethylene Oxide, Acetone and Propanal toward the Low-mass Protostar IRAS 16293–2422
Astrophys. J. 597, Art. No. A53 (2017).
This report is the first one on the detection of acetone around a low-mass protostar. The Protostellar Interferometric Line Survey (PILS) was carried out with ALMA in its Band 7 (329 – 363 GHz). A total of 186 lines were assigned to acetone.

Contributor(s): H. S. P. Müller; 02, 2006; 01, 2017