  We investigate the cosmological and astrophysical constraints on
superconducting cosmic strings (SCSs). SCS loops emit strong bursts of
electromagnetic waves, which might affect various cosmological and
astrophysical observations. We take into account the effect on the CMB
anisotropy, CMB blackbody spectrum, BBN, observational implications on radio
wave burst and X-ray or gamma-ray events, and stochastic gravitational wave
background measured by pulsar timing experiments. We then derive constraints on
the parameters of SCS from current observations and estimate prospects for
detecting SCS signatures in on-going observations. As a result, we find that
these constraints exclude broad parameter regions, and also that on-going radio
wave observations can probe large parameter space.
