  Telescope Array (TA) is the largest experiment in the Northern Hemisphere
studying ultrahigh energy cosmic rays. TA measurements of the cosmic ray
spectrum using the surface detector have the best statistical power in the
experiment, and observe the ankle of the spectrum and the high energy cutoff.
When the data are divided into two declination bands, above and below 24.8
degrees, the cutoff appears at $10^{19.64 \pm 0.04}$ ($10^{19.84 \pm 0.02}$) eV
in the lower (higher) band, an energy difference of 58\%. The global
significance of the difference is 4.3 standard deviations. The lack of an
instrumental cause of this difference implies it is astrophysical in nature.
