Overview

• The peer-reviewed analysis in Astronomy & Astrophysics, led by Trinity College Dublin’s Exo‑Aimsir group, reexamines JWST’s rotation-resolved spectra of SIMP‑0136.
• Observations reveal a thermal inversion with hotter upper layers plus sub‑5 °C temperature mapping that tracks chemistry changes across the object’s rapid 2.4‑hour rotation.
• Spectra indicate largely global, silicate (sand-like) clouds with minimal variability, contrasting with earlier expectations of patchy coverage.
• Evidence favors auroral heating of the stratosphere despite the lack of a stellar wind, though direct auroral confirmation in UV remains outstanding and prior radio pulses support the magnetic activity picture.
• SIMP‑0136 lies roughly 20–21 light-years away with an estimated mass near 12.7–15 Jupiter masses, and upcoming ELT and Roman observations are expected to probe its magnetic and auroral properties further.