We present a glimpse at a wide field optical Halpha/[SII] survey for HH objects covering ~5 square degrees in Orion A (so far). The survey uses the Wide-Field-Imager at the MPG 2.2m telescope on La Silla. First epoch observations were taken in 1999-2001 over ~1.5 square degrees. In 2023-2024 we secured second epoch observations of the initial coverage and significantly extended the survey (to about 5 square degrees).
The goal of the survey is to provide an unbiased wide field census of the outflow activity generated by the YSO population in the cloud, including shocks created far off the main cloud, and an unbiased overview of outflow velocities for a significant number of flows. This will help to complete the account of momentum and energy delivered by protostellar outflows and to quantify the fraction of the momentum/energy that might get "lost" to the surrounding ISM, i.e., would not contribute to protostellar outflow generated feedback.
We will showcase a selection of newly discovered HH flows as well as a first go at deriving proper motions for the HH43-38 giant Herbig Haro flow.
