Detection of silicates in the Beta Pictoris disk

A broad 10-micron emission feature has been detected within 3 arcsec of the star Beta Pic which is known to have a circumstellar, possibly protoplanetary, disk. The observations were made using four narrow-band filters in the MSFC bolometer array at the IRTF. The emission feature closely resembles silicate features observed in Comets Halley and Kohoutek and in a variety of Galactic sources. The feature is strong, with the total flux density emitted by dust at 10.3 microns being at least twice the estimated continuum at that wavelength, and must be emitted by particles with characteristic radii less than 10 microns.