Compact Subarcsec Structures of the Double Nucleus of NGC6240 Revealed with HST

We have used the Faint Object Camera on board of the Hubble Space Telescope to obtain a high spatial resolution ultraviolet image of the central region of NGC 6240. This image resolves the well known double nucleus of the galaxy into several compact knots with sizes 0.1''-0.2'' (about 45-90 pc for H_0_ = 75 km s^-1^Mpc^-1^) and extended low surface brightness emission. The northern (fainter) component B of the double nucleus of the galaxy contains only one bright compact source while the southern (brighter) component A consists of a string of bright knots plus more conspicuous extended emission than B. Evidence is presented that an appreciable fraction (if not all) of the compact emission is continuum light. The distance between the compact sources in A and B exceeds the distance between the corresponding 2 cm radio sources by ~0.5". A comparison with precise optical coordinates shows that the compact sources do not coincide with the radio sources. Extinction by molecular clouds between A and B might explain why there are no counterparts of the radio sources visible at shorter wavelengths. The presence of an elliptical bubble of size ~190 x 150 pc within an emitting region on the southwest of A could be due to multiple supernova explosions.