  We suggest that the unusual events observed by the ANITA experiment originate
from axion particles traversing the Earth. Under the influence of the
geomagnetic field, the axion may oscillate into a photon and vice-versa. To
amplify the axion transition into photon, we consider that the phenomenon takes
place at resonance, where the effective photon mass is equal to the axion mass.
This requirement fixes the axion mass at 200 eV. An axion at this mass scale
reproduces the cold dark matter scenario. If our interpretation prevails, with
the help of axions we can establish an axion tomography of the Earth.
