The Spatial-Kinematic Structure of the Region of Massive Star Formation
  S255N on Various Scales
  The results of a detailed analysis of SMA, VLA, and IRAM observations of the
region of massive star formation S255N in CO(2---1), \nh, \nhh, \co and some
other lines is presented. Combining interferometer and single-dish data has
enabled a more detailed investigation of the gas kinematics in the moleclar
core on various spatial scales. There are no signs of rotation or isotropic
compression on the scale of the region as whole. The largest fragments of gas
($\approx$0.3 pc) are located near the boundary of the regions of ionized
hydrogen S255 and S257. Some smaller-scale fragments are associated with
protostellar clumps. The kinetic temperatures of these fragments lie in the
range 10---80 K. A circumstellar torus with inner radius R$_{in}$ $\approx$
8000 AU and outer radius R$_{out}$ 12 000 AU has been detected around the clump
SMA1. The rotation profile indicates the existence of a central object with
mass $\approx$ 8.5/ sin 2 (i) M$_\odot$ . SMA1 is resolved into two clumps,
SMA1---NE and SMA1---SE, whose temperatures are $\approx$150 K and $\approx$25
K, respectively. To all appearances, the torus is involved in the accretion of
surrounding gas onto the two protostellar clumps.
