Abundant hydrocarbons in the disk around a very-low-mass star

NASA press Release

ESA Press Release

Astrobiology

The spectrum of the star ISO-ChaI 147 revealed by NASA’s James Webb Space Telescope’s MIRI (Mid-Infrared Instrument) shows the richest hydrocarbon chemistry seen to date in a protoplanetary disk, consisting of 13 carbon-bearing molecules. This includes the first extrasolar detection of ethane (C2H6). The team also successfully detected ethylene (C2H4), propyne (C3H4), and the methyl radical CH3, for the first time in a protoplanetary disk.
NASA, ESA, CSA, Ralf Crawford (STScI)

Very-low-mass stars (those less than 0.3 solar masses) host orbiting terrestrial planets more frequently than other types of stars. The compositions of those planets are largely unknown but are expected to relate to the protoplanetary disk in which they form. We used James Webb Space Telescope mid-infrared spectroscopy to investigate the chemical composition of the planet-forming disk around ISO-ChaI 147, a 0.11-solar-mass star. The inner disk has a carbon-rich chemistry; we identified emission from 13 carbon-bearing molecules, including ethane and benzene. The high column densities of hydrocarbons indicate that the observations probe deep into the disk. The high carbon-to-oxygen ratio indicates radial transport of material within the disk, which we predict would affect the bulk composition of any planets forming in the disk.

Abundant hydrocarbons in the disk around a very-low-mass star. By: A. Arabhavi et al. [original]