The disk-outflow system in the S255IR area of high mass star formation and major scientific drivers for the Millimetron space telescope

A major unsolved problem of high mass star formation is the characterization
of accretion disks around young high-mass protostars. S255 is an H II region
associated with a rather well studied area of massive star formation which
consists of two main components (S255IR and S255N) separated by slightly
over 1'. Our and other data indicate a presence of a rotating core and a
spectacular molecular outflow in the S255IR area. Recently we observed this
region with the Submillimeter Array (SMA) at 1.3 mm with the 0.4 arc sec
resolution and at 0.8 mm with the 2 arc sec resolution in continuum and
in various molecular lines. In addition some of these lines were observed
at the IRAM-30m telescope. The combination of the single-dish and
interferometric data helps to understand better the structure of the sources.
Here we discuss the morphology, kinematics and physical properties of the
dense core and outflow derived from these observations.

Millimetron is the project of a large (10 m in diameter) cooled space
submillimeter telescope. The dish will be cooled passively to about 50 K and
actively to about 4.5 K which will provide unprecedented sensitivity. Here we
give a brief overview of the main scientific tasks for this mission, mainly in
the field of interstellar medium and star formation studies.