  Orbiting $\gamma$-detectors combined with the magnetic field of the Earth or
the Sun can work parasitically as cosmic axion telescopes. The relatively short
field lengths allow the axion-to-photon conversion to be coherent for
$m_{axion} \sim 10^{-4}$ eV, if the axion kinetic energy is above $\sim 500$
keV (Earth's field), or, $\sim 50$ MeV (Sun's field), allowing thus to search
for axions from $e^+e^-$ annihilations, from supernova explosions, etc. With a
detector angular resolution of $\sim 1^o$, a more efficient sky survey for
energetic cosmic axions passing {\it through the Sun} can be performed. Axions
or other axion-like particles might be created by the interaction of the cosmic
radiation with the Sun, similarly to the axion searches in accelerator beam
dump experiments; the enormous cosmic energy combined with the built-in
coherent Primakoff effect might provide a sensitive detection scheme, being out
of reach with accelerators. The axion signal will be an excess in $\gamma$-rays
coming either from a specific celestial place behind the Sun, e.g. the Galactic
Center, or, from any other direction in the sky being associated with a violent
astrophysical event, e.g. a supernova. Earth bound detectors are also of
potential interest. The axion scenario also applies to other stars or binary
systems in the Universe, in particular to those with superstrong magnetic
fields.
