  Images in the J, H and K bands and in the the v=1-0 S(1) line of H2 of the
central region of the almost edge-on galaxy NGC 3079 reveal contributions from
direct and scattered starlight, emission from hot dust and molecular gas, and
extinction gradients. The central 100 pc suffers an extinction of 6 mag.
Extremely red near-infrared colours require the presence of hot dust at about
1000 K. Less reddened parts of the bulge require either a 20% J-band
contribution from young stars in a stellar bar, or a 20-30% contribution from
scattered stellar light.
  The nucleus is surrounded by a dense molecular disk of radius 300 pc.
Emission from H2 and hot dust traces a cavity of radius 120 pc. In the central
few hundred pc, HI spin temperatures must be less than 275 K and the CO-to_H2
conversion factor is at most 5% of the standard Galactic value. This is
consistent with theoretical predictions for environments subjected to
dissociative shocks, where reformation of H2 is impeded by high dust grain
temperatures. The overall molecular gas content of NGC 3079 is normal for a
late-type galaxy.
