We present unpublished Spitzer IRAC observations of the HH 1/2 young stellar outflow processed with a high angular resolution deconvolution algorithm , that produces sub-arcsecond ( \sim 0.6 - 0.8 \arcsec ) images .
In the resulting mid-infrared images , the optically invisible counterjet is detected for the first time .
The counterjet is approximately half as bright as the jet at 4.5 \mum ( the IRAC band that best traces young stellar outflows ) and has a length of \sim 10 ^ { \prime \prime } .
The NW optical jet itself can be followed back in the mid-IR to the position of the exciting VLA 1 source .
An analysis of the IRAC colors indicates that the jet/counterjet emission is dominated by collisionally excited H _ { 2 } pure rotational lines arising from a medium with a neutral Hydrogen gas density of \sim 1000 - 2000 cm ^ { -3 } and a temperature \sim 1500 K. The observed jet/counterjet brightness asymmetry is consistent with an intrinsically symmetric outflow with extinction from a dense , circumstellar structure of \sim 6 ^ { \prime \prime } size ( along the outflow axis ) , and with a mean visual extinction , A _ { V } \sim 11 mag .