If the usual equipartition assumptions are made, then it is possible to
estimate the magnetic field strength and pressure in the lobes.
Assuming that the observed spectral index is maintained from 10 MHz to
100 GHz, that there are equal energies in the radiating electrons and
other particles, and that the filling factor is unity, the derived
magnetic field is B_{min} ~ 5 × 10^{-6} h_{50}^{2/7} Gauss
and p_{min} ~ 3.5 × 10^{3} h_{50}^{4/7} cm^{-3} K for the
hot spots. At the midpoint of the lobes these values are
B_{min} ~ 8 × 10^{-7} h_{50}^{2/7} Gauss and
p_{min} ~ 2.3 × 10^{2} h_{50}^{4/7} cm^{-3} K. At this
redshift, the 3 K microwave background has an equivalent magnetic field
of 4.2× 10^{-6} Gauss so the energy loss in the lobes should be
dominated by inverse Compton scattering of this background, and the
time for the electrons radiating at 1400 MHz to lose half of their
energy will be ~ 10^{8} h_{50}^{-3/7} years.