Identification of Polycyclic Aromatic Molecules in the UV Spectrum of Comet P/Halley

Emission spectra of comet P/Hallev in the 275–710 nm wavelength range were obtained by using a spectrometer carried on board the Vega 2 spacecraft which encountered the famous comet on March 9, 1986. The spectrum, after subtraction of the intense solar continuum, shows the presence of two new spectral features: An isolated band at 323 nm and a broad band with four peaks at 347, 356, 364 and 374 nm. We compared our cometary spectra with UV laboratory spectra of polycyclic aromatic hydrocarbons having 2 and 3 benzenoid rings. We can securely propose the identification of phenanthrene and suggest the presence of naphthalene in Halley's comet. © 1995, Taylor & Francis Group, LLC. All rights reserved.

Duke Scholars

Author Tuan Vo-Dinh Biomedical Engineering