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Proper motions have been measured on Crossley and 120-in. plates for additional Herbig-Haro Objects. The bright, nearly stellar HH-11 shows definite motion away from the heavily obscured H2O maser and infrared source SSV-13, about 16 arc sec distant. Three other nearby Objects show no detectable motions. Repetitive ejection from the vicinity of SSV-13 at intervals of greater than 500 years is suggested. Nuclei in the nearby extended object HH-12 show motion away from another obscured star, SSV-11, of type M1e-alpha. The indicated travel time is 800-1400 years. All these Objects have negative radial velocities with respect to the molecular cloud, and lie in regions of negative CO velocity. No Objects have been found on the opposite sides of the exciting stars, where the velocity would presumably be positive. HH-32A, B are moving away from the bright T Tauri star AS-353A, and have both large positive velocities and double emission lines. The line splitting is interpreted in terms of pre- and post-shock gas on the front side of an (invisible) obstacle in the wind from AS-353A.
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Herbig et al. (1983) studied this question.
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