SARG-TNG spectra play a key role in the discovery of naphtalene in the interstellar space

Spanish researchers have succeeded in identifying naphthalene, one of the most complex molecules yet discovered in the interstellar medium.

The naphthalene was discovered in a star formation region in the constellation Perseus, in the direction of the star Cernis 52. The spectral bands found in this constellation coincide with laboratory measurements of the naphthalene cation. Optical spectra taken with SARG at TNG in November 2006 provided the first evidence of the presence of the naphthalene. Subsequently, spectra obtained with other telescopes confirmed the results obtained with SARG.

The detection of naphtalene suggests that a large number of the key components in prebiotic terrestrial chemistry could have been present in the interstellar matter from which the Solar System was formed. In fact, when subjected to ultraviolet radiation and combined with water and ammonium (both abundant in the space between the stars), naphthalene reacts and is capable of producing a wide variety of aminoacids and naphthaloquinones, precursor molecules to vitamins.

All these molecules play a fundamental role in the development of life as we know it on Earth. In fact, naphthalene has been found in meteorites that continue to fall to the surface of Earth, and which fell with much greater intensity in epochs preceding the appearance of life.

(S. Iglesias Groth et al., "Evidence for the naphtalene cation in a region of the interstellar medium with anomalous microwave emission", 2008, Astrophysical Journal, vol. 685, pages 55-58)

Artist's impression of the planet around V391 Pegasi
Figure 1. DSS2 R-band image of Cernis 52 with, superimposed, a picture of the molecule of naphtalene.