• Interpretation

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        * If the proper motions of the HH objects are extended backwards, they intersect near the infrared source, which implies that they have been accelerated by a strong stellar wind from IRS-5. The ~150 km/sec HH object transverse velocities imply a stellar wind velocity greater than 200 km/sec.

        * The spectra of HH objects resemble that of a shocked gas. Two models explain the origin of the emission:
    a) Bow shocks, which form when strong stellar winds interact with dense clumps of gas (Schwartz, 1978).
    b) Shocks, which form when strong stellar wind accelerates dense condensations and ejects them into the surrounding cloud (Norman and Silk, 1979)

        * The authors model the broad velocity features by a dense shell of gas which has been swept out by the stellar wind. The wind directs materials NE and SW of the infrared source and could be confined by a thick accretion disk around IRS-5. The two lobes are also oriented along the magnetic field direction.

        * The velocity of the shell is 15 km/sec into the molecular cloud. H2 emission cools  the gas behind the shock to temperatures < 500K. The data suggest that most of the CO emission comes from 8-35 K temperature gas. Its age is roughly 30,000 years.
     

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