Webb Telescope Discovers Key Carbon Compound

These Webb images show a part of the Orion Nebula known as the Orion Bar. At upper right, the telescope is focused on a smaller area using Webb’s MIRI (Mid-Infrared Instrument). At the very center of the MIRI area is a young star system with a protoplanetary disk named d203-506. The pullout at the bottom right displays a combined NIRCam and MIRI image of this young system. Credits: ESA/Webb, NASA, CSA, M. Zamani (ESA/Webb), and the PDRs4All ERS Team

Key points:

• Methyl cation (CH₃⁺) was spotted in the protoplanetary disk of a small red dwarf
• CH₃⁺ is an important precursor to the formation of more complex organic molecules
• The discovery provides insights into the potential early chemical origins of life

An international team has used NASA’s James Webb Space Telescope to discover a crucial carbon compound in space for the first time. The compound is a key precursor to the formation of more complex carbon molecules and its discovery could provide insights into life’s chemical beginnings.

The researchers spotted methyl cation (CH₃⁺) in the protoplanetary disk of a small red dwarf in the Orion Nebula. The disk, called d203-506 and located about 1,350 light-years from Earth, receives strong ultraviolet radiation from larger stars nearby.

While UV radiation typically destroys complex carbon molecules, the researchers believe this protoplanetary environment may provide the energy needed for CH₃⁺ formation. The team also predicts that most protoplanetary disks experience similar periods of intense UV exposure, as stars tend to form in groups that include more massive stars.

The researchers leveraged the excellent spatial and spectral resolution of the Webb telescope to make their discovery. Webb’s detection of key emission lines confirmed the identification of CH₃⁺.

The team’s paper in Nature notes the key role of CH₃⁺ in the development of complex organic compounds. The authors also noted that the chemical environment of d203-506 differs from that of typically observed protoplanetary disks and contains no water. Lead author Olivier Berné, of the French National Centre for Scientific Research in Toulouse, said this shows how UV radiation can transform protoplanetary chemistry and potentially set the stage for life’s chemical precursors.

“This detection not only validates the incredible sensitivity of Webb but also confirms the postulated central importance of CH₃⁺ in interstellar chemistry,” added coauthor Marie-Aline Martin-Drumel of the University of Paris-Saclay.

The research, part of the PDRs4ALL Early Release Science program, provides fresh insights into interstellar organic chemistry that could eventually help scientists trace the beginnings of life on Earth and the universe.