Observational signatures of traversable wormholes*

Abstract This study investigates the observational signatures of traversable Simpson-Visser wormholes illuminated by luminous celestial spheres and orbiting hot spots. We demonstrate that when light sources and observers are on the same side of a wormhole, the images of the wormhole mimic those of a black hole. However, when the light source is positioned opposite the observer, photons traversing the wormhole throat generate distinct observational signatures. Specifically, unlike black hole images, wormhole images are confined in a critical curve, resulting in smaller centroid variations. Furthermore, the light curve of hot spots can exhibit additional peaks.