LOFAR image of J0011+3217 at 144 MHz. The contour levels are at 0.23, 0.45, 0.75, 1.17, 1.75, 2.57, 3.72, 5.33, 7.58, 10.7, 15.1, 21.3, 30.0, 42.1, and 59.0 mJy beam⁻¹. The lowest contour level of J0011+3217 is at 3σ, where σ = 78 μJy beam⁻¹ is the mean RMS around the source. The white circle in the left corner of the image represents the synthesised beam of J0011+3217 with 6″ × 6″ resolution.