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Discovery of X-rays from the protostellar outflow object HH2
S H Pravdo1, E D Feigelson, G Garmire
1Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 306-438, 4800 Oak Grove Drive, Pasadena, California 91109, USA. spravdo@jpl.nasa.gov
Nature
|October 19, 2001
Summary
Astronomers detected X-rays from Herbig-Haro (HH) objects, confirming shock-heated gas in these star-forming regions. This discovery supports the jet-induced shock model for HH object formation.
Area of Science:
- Astrophysics
- Astronomy
- Stellar Evolution
Background:
- Herbig-Haro (HH) objects are luminous gas condensations in star-forming regions.
- Their physical nature has been debated, with models including newborn stars, stellar winds, and shock-excited gas pockets.
- The jet-induced shock model predicts X-ray emission from energetic HH objects.
Purpose of the Study:
- To investigate the presence of X-ray emission from Herbig-Haro objects.
- To test the predictions of the jet-induced shock model.
Main Methods:
- Observation of the Herbig-Haro object HH2, one of the brightest and closest.
- Analysis of X-ray emission levels and comparison with theoretical models.
Main Results:
- X-ray emission was detected from the Herbig-Haro object HH2.
- The detected X-ray levels align with predictions from the jet-induced shock model.
- The emission originates from shock-heated material at the object's leading edge.
Conclusions:
- The discovery provides strong evidence for the jet-induced shock model.
- Herbig-Haro objects contain shock-heated material with temperatures around 10^6 K.
- This finding advances our understanding of the physical processes in star formation.
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