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Context. Red supergiant stars possess surface features and extended molecularatmospheres. Photospheric convection may be a crucial factor of the levitationof the outer atmospheric layers. However, the mechanism responsible is stillpoorly understood. Aims. We image the stellar surface of V602 Carinae (V602Car) to constrain the morphology and contrast of the surface features and ofthe extended atmospheric layers. Methods. We observed V602 Car with the VeryLarge Telescope Interferometer (VLTI) PIONIER instrument (1.53-1.78$\mathrm{\mu}$m) between May and July 2016, and April and July 2019 withdifferent telescope configurations. We compared the image reconstructions with81 temporal snapshots of 3D radiative-hydrodynamics (RHD) CO$^5$BOLDsimulations in terms of contrast and morphology, using the StructuralSimilarity Index. Results. The interferometric data are compatible with anoverall spherical disk of angular diameter 4.4$\pm$0.2 mas, and an extendedmolecular layer. In 2016, the reconstructed image reveals a bright arc-likefeature toward the northern rim of the photospheric surface. In 2019, anarc-like feature is seen at a different orientation and a new peak of emissionis detected on the opposite side. The contrasts of the reconstructed surfaceimages are 11%$\pm$2% and 9%$\pm$2% for 2016 and 2019, respectively. Themorphology and contrast of the two images are consistent with 3D RHDsimulations, within our achieved spatial resolution and dynamic range. Theextended molecular layer contributes 10--13% of the total flux with an angulardiameter of 6--8 mas. It is present but not clearly visible in thereconstructed images because it is close to the limits of the achieved dynamicrange. The presence of the molecular layer is not reproduced by the 3D RHDsimulations. Conclusions...

VLTI-PIONIER imaging of the red supergiant V602 Carinae