Under standard conditions in the laboratory, vinyl cyanide is a colorless liquid that is highly flammable and toxic. It is commonly observed by radio astronomers in the “hot cores” of interstellar clouds, which are the sites of the formation of massive stars, and it has also been detected at lower abundance in cold interstellar clouds and in the envelopes of evolved, carbon-rich stars. Observations at millimeter wavelengths detect the pure rotational transitions in the ground vibrational state and in low-lying vibrational states; 13-carbon isotopic species have also been detected in molecular clouds (Müller et al. 2008).
Interstellar vinyl cyanide was first detected by Gardner and Winnewisser (1975).