Continuum (1.3 mm) and J = 2 − 1 ¹³CO, C¹⁸O, and C¹⁷O line emission towards Hen 3-1475. Left: Maps of the continuum (colour map) and high-velocity line emission (contours). The continuum peaks at $\alpha ={17}^{\text{h}}{45}^{\text{m}}14\stackrel{\text{s}}{.}177$ and $\delta =-{17}^{°}56\prime 46\stackrel{″}{.}895$. The full, dashed and dotted lines show emission in the ¹³CO J = 2 − 1 integrated over the spectral intervals at increasingly large expansion velocities marked in dark grey, grey, and light grey, respectively, in the line plots. Magenta and cyan contours mark red-shifted and blue-shifted emission, respectively, at 10%, 30%, 50%, and 70% of the peak value of each emission component. The 10% value of the most extreme emission is not shown because it is comparable to the noise level. The peak values for the dark grey, grey, and light grey spectral regions are, respectively, 0.0422, 0.0122, and 0.0030 Jy beam⁻¹ × km s⁻¹ for the redshifted emission and 0.0205, 0.0156, and 0.0083 Jy beam⁻¹ × km s⁻¹ for the blue-shifted emission. Middle: Source-integrated spectra of the ¹³CO J = 2 − 1, C¹⁸O J = 2 − 1, and C¹⁷O J = 2 − 1 lines. Right: Source-integrated spectrum of the ¹³CO J = 2 − 1 line showing the very-high-velocity components extracted using a rectangular aperture of $3\stackrel{″}{.}5\times 17″$ and oriented along the high-velocity-emission direction.