  The Becklin-Neugebauer (BN) object in the Orion Nebula Cluster (ONC) is a
well-studied optically invisible, infrared-bright young stellar object, thought
to be an intermediate-mass protostar. We report here that BN exhibited
nearly-sinusoidal periodic variability at the near-infrared H- and Ks-bands
during a one month observing campaign in 2000 March/April. The period was 8.28
days and the peak-to-peak amplitude ~0.2 mag. Plausible mechanisms for
producing the observed variability characteristics are explored.
