HH Bow Shocks Resolved with UFTI

Images of the Herbig-Haro objects HH 7-11 (above) and HH 33 (below) were obtained through the H₂ filter using UFTI in October 1998. The two main bow shocks (best seen in the two contour plots) represent shock fronts produced as narrow jets push their way through the surrounding molecular cloud (much like the bow wave formed at the front of a ship as it steams through the ocean). The shocks compress and heat ambient gas so that it radiates in molecular hydrogen emission; this allows us to observe each shock directly. The (unseen) jets themselves are driven by stars that are still forming deep inside the cloud. The figures show how remarkably thin bow shocks can be. Image courtesy of Jason Hobson, Antonio Chrysostomou and Chris Davis (JAC).