Detection of C ₆₀ and C ₇₀ in a Young Planetary Nebula

Abstract

In recent decades, a number of molecules and diverse dust features have been identified by astronomical observations in various environments. Most of the dust that determines the physical and chemical characteristics of the interstellar medium is formed in the outflows of asymptotic giant branch stars and is further processed when these objects become planetary nebulae. We studied the environment of Tc 1, a peculiar planetary nebula whose infrared spectrum shows emission from cold and neutral C60 and C70. The two molecules amount to a few percent of the available cosmic carbon in this region. This finding indicates that if the conditions are right, fullerenes can and do form efficiently in space.

Gas Phase Absorption Spectroscopy of and in a Cryogenic Ion Trap: Comparison With Astronomical Measurements*

“…Both C 60 and C 70 have been detected via infrared emission in a young planetary nebula (Cami et al 2010), and since then in a variety of other environments (see, for example, Roberts et al 2012 and references therein). Thus the presence of + C 70 is also expected in the diffuse medium.…”

Astrochemistry of dust, ice and gas: introduction and overview

“…At the opposite end of the size range of interstellar molecules, C 60 and C 70 have recently been identified in a young planetary nebula through infrared spectroscopy 5 . Other large molecules such as PAHs are also inferred to be present based on the ubiquitous set of mid-infrared bands that are observed throughout the Universe and which can be ascribed to aromatic C=C and C-H bonds 2 .…”

“…In star-forming clouds within our Galaxy, a myriad of species has been found, some of which are prebiotic, i.e., molecules that are thought to be involved in the processes leading to living organisms. Fullerenes such as C 60 have also been identified 5 . Finally, simple molecules including H 2 O are being detected in the atmospheres of giant exo-planets 6,7 .…”

Redshifted diffuse interstellar bands in the Orion OB1 association

“…Some of these species have recently been observed in the middle and far infrared by the space telescope Herschel. The largest currently known interstellar molecules are the fullerenes C60 and C70 (Cami et al 2010;Berné et al 2013). Yet unknown (unidentified) molecular species are believed to be the carriers of diffuse interstellar bands (DIBs): these make up the longest standing unsolved problem in astronomical spectroscopy.…”