# The Dusty Silhouette Jet HH 1019 in the Carina Nebula

## TL;DR

The paper reports the discovery of HH 1019, a unique Herbig-Haro jet in the Carina Nebula characterized by a chain of dark dust knots seen in silhouette, providing new insights into dusty jet phenomena and their origins.

## Contribution

It introduces HH 1019 as a new subclass of dusty Herbig-Haro objects, observed primarily in silhouette against a bright H II region, and discusses its implications for jet launching from various disk radii.

## Key findings

- HH 1019 is a bipolar collimated jet with dark dust knots in silhouette.
- Proper motions confirm high-speed movement of dust condensations.
- The jet's high extinction suggests dust lifted from the disk or entrained from the envelope.

## Abstract

We report the discovery in Hubble Space Telescope (HST) images of the new Herbig-Haro jet, HH 1019, located near the Tr 14 cluster in the Carina Nebula. Like other HH jets in the region, this bipolar collimated flow emerges from the head of a dark dust pillar. However, HH 1019 is unique because -- unlike all other HH jets known to date -- it is identified by a linear chain of dark, dusty knots that are seen primarily in silhouette against the background screen of the H II region. Proper motions confirm that these dark condensations move along the jet axis at high speed. [S II] emission traces a highly collimated jet that is spatially coincident with these dust knots. The high extinction in the body of the jet suggests that this outflow has lifted a large amount of dust directly from the disk, although it is possible that it has entrained dust from its surrounding protostellar envelope before exiting the dust pillar. If dust in HH 1019 originates from the circumstellar disk, this provides further evidence for a jet launched from a range of radii in the disk, including those outside the dust sublimation radius. HH 1019 may be the prototype for a new subclass of dusty HH objects seen primarily in extinction against the background screen of a bright H II region. Such jets may be common, but difficult to observe because they require the special condition of a very bright background in order to be seen in silhouette.