  We report the discovery of a z~9 Lyman Break Galaxy (LBG) candidate, selected
from the NICMOS Parallel Imaging Survey as a J-dropout with J110 - H160 = 1.7.
Spitzer/IRAC photometry reveals that the galaxy has a blue H160 - 3.6 um color,
and a spectral break between 3.6 and 4.5 um. We interpret this break as the
Balmer break, and derive a best-fit photometric redshift of z~9. We use Monte
Carlo simulations to test the significance of this photometric redshift, and
show a 96% probability of z>7. We estimate a lower limit to the comoving number
density of such galaxies at z~9 of phi > 3.8 x 10^{-6} Mpc^{-3}. If the high
redshift of this galaxy is confirmed, this will indicate that the luminous end
of the rest-frame UV luminosity function has not evolved substantially from z~
9 to z~3. Still, some small degeneracy remains between this z~9 model and
models at z~2-3; deep optical imaging (reaching I ~ 29 AB) can rule out the
lower-z models.
