Sub-arcsecond scale Keck images of the young A1V star , 49 Ceti , resolve emission at \lambda = 12.5 and 17.9  \mu m from a disk with long axis at PA 125 \pm 10 ^ { \circ } and inclination \phi = 60 \pm 15 ^ { \circ } .
At 17.9 \mu m , the emission is brighter and more extended toward the NW than the SE .
Modeling of the mid-infrared images combined with flux densities from the literature indicate that the bulk of the mid-infrared emission comes from very small grains ( a \sim 0.1 \mu m ) confined between 30 and 60 AU from the star .
This population of dust grains contributes negligibly to the significant excess observed in the spectral energy distribution .
Most of the non-photospheric energy is radiated at longer wavelengths by an outer disk of larger grains ( a  \sim 15 \mu m ) , inner radius \sim 60 AU , and outer radius \sim 900 AU .
Global properties of the 49 Cet disk show more affinity with the \beta Pic and HR 4796A disks than with other debris disks .
This may be because they are all very young ( t < 20 Myr ) , adding strength to the argument that they are transitional objects between Herbig Ae and “ Vega-like ” A stars with more tenuous circumstellar disks .