IIA scientists use JWST data to find complex hydrocarbons lit up around young star T Chamaeleontis
Scientists of the Indian Institute of Astrophysics used archival JWST data to detect PAH molecules glowing in the planet-forming disk of the young star T Chamaeleontis after part of its inner wall collapsed, DST said on 26 December 2025.
Summary
Scientists of the Indian Institute of Astrophysics (IIA), an autonomous institute of the Department of Science and Technology, used archival data from the Mid Infrared Instrument (MIRI) of NASA's James Webb Space Telescope to study polycyclic aromatic hydrocarbons (PAHs) around the young star T Chamaeleontis (T Cha), DST said on 26 December 2025. T Cha, about 350 light-years away, has a planet-forming disk with a wide gap; when part of the disk's inner wall collapsed during a burst of accretion, ultraviolet light flooded the outer disk and made the PAHs glow strongly in JWST's 2022 observations. The IIA team also found faint PAH signatures in archival Spitzer data, the first confirmed detection in Spitzer's spectrum of T Cha, and reported that the PAHs have fewer than 30 carbon atoms; the study was published in the Astronomical Journal.
Key facts
- Institute
- Indian Institute of Astrophysics (IIA), autonomous institute of DST
- Star
- T Chamaeleontis (T Cha), about 350 light-years away
- Data
- Archival JWST MIRI (2022) and Spitzer (2002) spectra
- Molecules
- PAHs (polycyclic aromatic hydrocarbons), fewer than 30 carbon atoms
- Trigger
- Partial collapse of disk's inner wall during an accretion burst
- Journal
- Astronomical Journal
Practice MCQs 2 questions
Data from which instrument did Indian Institute of Astrophysics scientists use to study PAH molecules around the young star T Chamaeleontis?
Show answer
Correct answer: B — Mid Infrared Instrument (MIRI) of JWST
PIB 2208927: IIA scientists used archival spectroscopic data from JWST's Mid Infrared Instrument (MIRI).
Consider the following statements about the IIA study of T Chamaeleontis released in December 2025: 1. T Chamaeleontis is a young star about 350 light-years from Earth. 2. The PAH molecules found contain more than 100 carbon atoms each. 3. Faint PAH signatures were also found in archival Spitzer Space Telescope data. Which of the statements given above is/are correct?
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Correct answer: D — 1 and 3 only
PIB 2208927: T Cha is about 350 light-years away and faint PAH signatures were found in archival Spitzer data. The PAHs are smaller molecules with fewer than 30 carbon atoms, so statement 2 is wrong.