# Discovery of X-rays from the protostellar outflow object HH2

@article{Pravdo2001DiscoveryOX,
title={Discovery of X-rays from the protostellar outflow object HH2},
author={Steven H. Pravdo and Eric D. Feigelson and Gordon P. Garmire and Yoshitomo Maeda and Yohko Tsuboi and J. M. Bally},
journal={Nature},
year={2001},
volume={413},
pages={708-711}
}
• Published 18 October 2001
• Physics
• Nature
Herbig–Haro (HH) objects have been known for 50 years to be luminous condensations of gas in star-forming regions, but their underlying physical nature is still being elucidated. Previously suggested models encompass newborn stars, stellar winds clashing with nebular material, dense pockets of interstellar gas excited by shocks from outflows, and interstellar ‘bullets’ (ref. 6). Recent progress has been made with the jet-induced shock model, in which material streams out of young stellar…
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