Average transmission spectrum of WASP-69b in the planet rest frame in black. The blue curve is the best-fit model from the thermosphere only, while the red curve is the best-fit model from the thermosphere and exosphere. Spectra between t₁ and t₄ were used to built the transmission spectrum. The vertical blue dashed lines indicate the helium lines’ positions. The bump at 10 835 Å is likely due to telluric residuals.