G359.87- A YOUNG SUPERNOVA REMNANT CANDIDATE NEAR THE GALACTIC-CENTER(0.18 )

Subarcsecond radio continuum observations of the Galactic center regio n at lambda = 6 and 2 cm reveal a 0 ''.5 diameter source with a shell- like morphology. This source is linearly polarized at a level of 16% a t 6 cm and has a steep nonthermal spectrum with a spectral index of 1. 6 between 6 and 2 cm. The distance to this source is not known, but th e large rotation measure value of 3000 rad m(-2) suggests that G359.87 +0.18 is likely to be located in the inner Galaxy or at an extragalact ic distance. We discuss possible interpretations of this object as a r ecent supernova, a very young supernova remnant, a nova remnant, or an extragalactic source. All possibilities are highly problematic.