We report the detection during the Chandra Orion Ultradeep Project ( COUP ) of two soft , constant , and faint X-ray sources associated with the Herbig-Haro object HH 210 .
HH 210 is located at the tip of the NNE finger of the emission line system bursting out of the BN-KL complex , northwest of the Trapezium cluster in the OMC-1 molecular cloud .
Using a recent H \alpha image obtained with the ACS imager on board HST , and taking into account the known proper motions of HH 210 emission knots , we show that the position of the brightest X-ray source , COUP 703 , coincides with the emission knot 154-040a of HH 210 , which is the emission knot of HH 210 having the highest tangential velocity ( 425 km s ^ { -1 } ) .
The second X-ray source , COUP 704 , is located on the complicated emission tail of HH 210 close to an emission line filament and has no obvious optical/infrared counterpart .
Spectral fitting indicates for both sources a plasma temperature of \sim 0.8 MK and absorption-corrected X-ray luminosities of about 10 ^ { 30 } erg s ^ { -1 } ( 0.5–2.0 keV ) .
These X-ray sources are well explained by a model invoking a fast-moving , radiative bow shock in a neutral medium with a density of \sim 12000 cm ^ { -3 } .
The X-ray detection of COUP 704 therefore reveals , in the complicated HH 210 region , an energetic shock not yet identified at other wavelengths .