  We report the discovery of a candidate galaxy with a photo-z of z~12 in the
first epoch of the JWST Cosmic Evolution Early Release Science (CEERS) Survey.
Following conservative selection criteria we identify a source with a robust
z_phot = 11.8^+0.3_-0.2 (1-sigma uncertainty) with m_F200W=27.3, and >7-sigma
detections in five filters. The source is not detected at lambda < 1.4um in
deep imaging from both HST and JWST, and has faint ~3-sigma detections in JWST
F150W and HST F160W, which signal a Ly-alpha break near the red edge of both
filters, implying z~12. This object (Maisie's Galaxy) exhibits F115W-F200W >
1.9 mag (2-sigma lower limit) with a blue continuum slope, resulting in 99.6%
of the photo-z PDF favoring z > 11. All data quality images show no artifacts
at the candidate's position, and independent analyses consistently find a
strong preference for z > 11. Its colors are inconsistent with Galactic stars,
and it is resolved (r_h = 340 +/- 14 pc). Maisie's Galaxy has log M*/Msol ~ 8.5
and is highly star-forming (log sSFR ~ -8.2 yr^-1), with a blue rest-UV color
(beta ~ -2.5) indicating little dust though not extremely low metallicity.
While the presence of this source is in tension with most predictions, it
agrees with empirical extrapolations assuming UV luminosity functions which
smoothly decline with increasing redshift. Should followup spectroscopy
validate this redshift, our Universe was already aglow with galaxies less than
400 Myr after the Big Bang.
