James Webb Space Telescope (JWST) detects organic molecules in planet-forming disk of star T Chamaeleontis (T Cha)

Key facts

• Astronomers studied the young, Sun-like star T Chamaeleontis (T Cha), which is located approximately 350 light-years from Earth.
• The James Webb Space Telescope (JWST) revealed the presence of complex organic molecules known as polycyclic aromatic hydrocarbons (PAHs) in the star's circumstellar disk.
• A sudden burst of accretion in 2022 caused the partial collapse of the disk’s inner wall, allowing ultraviolet (UV) radiation to illuminate previously hidden regions.
• The detection was made using the JWST’s Mid-Infrared Instrument (MIRI), which captured the PAH glow in the 5–15 microns wavelength range.
• Scientists from the Indian Institute of Astrophysics (IIA), an autonomous institute under the Department of Science and Technology (DST), led the analysis of the spectroscopic data.
• The study found that the PAHs in the T Cha disk are relatively small, containing fewer than 30 carbon atoms.
• Comparison with archival data from the Spitzer Space Telescope from 2002 showed that the intrinsic properties of the molecules remained stable over nearly two decades.
• The T Cha system contains a wide gap in its disk believed to have been carved out by an emerging protoplanet.