Rotational transitions of various isotopic forms of carbon monoxide (for example, 12CO, 13CO, and 18CO) are detectable in the submillimeter wavelength range, and are used in the study of newly forming stars in molecular clouds.
Roterende overgange af diverse isotopiske former for carbonmonoxid (for eksempel 12CO, 13CO og 18CO) kan ses i submillimeter-bølgelængdeområdet, og bruges i studiet af nyligt dannede stjerner i molekyleskyer.