  It has been recently reported that, at late times, the total luminosity of a
star freely falling in black holes decays exponentially with time, and one or
two series of flashes with decreasing intensity are seen by a specific
observer, depending on the number of photon spheres. In this paper, we examine
observational appearances of an infalling star in a reflection-asymmetric
wormhole, which has two photon spheres, one on each side of the wormhole. We
find that the late-time total luminosity measured by distant observers
gradually decays with time or remains roughly constant due to the absence of
the event horizon. Moreover, a specific observer would detect a couple of light
flashes in a bright background at late times. These observations would offer a
new tool to distinguish wormholes from black holes, even those with multiple
photon spheres.
