The James Webb Space Telescope has captured a beautiful juxtaposition of the nearby protostellar outflow known as Herbig-Haro 49/50 with a perfectly positioned, more distant spiral galaxy. Because of the proximity of this Herbig-Haro object to Earth, this new composite infrared image of the outflow from a young star allows researchers to study details at small spatial scales like never before.
With Webb, we can better understand how the jet activity associated with the formation of young stars can affect their surroundings.
This new composite image combines observations from Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument), providing a high-resolution view to explore the exquisite details of this bubbling activity.
Herbig-Haro 49/50 is located about 630 light-years from Earth in the constellation Chamaeleon. Herbig-Haro objects are outflows produced by jets ejected from a nearby forming star. The outflows, which can extend for light-years, plow into a denser region of material. This creates shock waves that heat the material to higher temperatures.
The material then cools by emitting light at visible and infrared wavelengths. When NASA’s Spitzer Space Telescope observed it in 2006, scientists nicknamed Herbig-Haro 49/50 (HH 49/50) the “Cosmic Tornado” because of its helical appearance, but they were uncertain about the nature of the fuzzy object at the tip of the “tornado”. With its higher imaging resolution, Webb provides a different visual impression of HH 49/50, revealing fine features of the shocked regions in the outflow, revealing the fuzzy object to be a distant spiral galaxy, and showing a sea of distant background galaxies.
HH 49/50 is located in the Chamaeleon I cloud complex, one of the closest active star formation regions in our Milky Way, producing numerous low-mass stars similar to our Sun. This cloud complex is probably similar to the environment in which our Sun formed. Previous observations of this region show that the HH 49/50 outflow is moving away from us at speeds of 100-300 kilometers per second and is only one feature of a larger outflow.
Webb’s NIRCam and MIRI observations of HH 49/50 trace the location of glowing hydrogen molecules, carbon monoxide molecules, and energized dust grains, shown in orange and red, as the protostellar jet slams into the region. Webb’s observations probe details on small spatial scales that will help astronomers model the properties of the jet and understand how it affects the surrounding material.
The arc-shaped features in HH 49/50, similar to a wake created by a speeding boat, point to the source of this outflow. Based on previous observations, scientists suspect that a protostar known as Cederblad 110 IRS4 is a plausible driver of the jet activity. Located about 1.5 light-years from HH 49/50 (in the lower right corner of the Webb image), CED 110 IRS4 is a Class I protostar. Class I protostars are young objects (tens of thousands to a million years old) in the prime of mass accretion. They usually have a discernible surrounding disk of material that is still falling onto the protostar. Scientists recently used Webb’s NIRCam and MIRI observations to study this protostar and take stock of the icy composition of its environment.
These detailed Webb images of the arcs in HH 49/50 can more accurately pinpoint the direction of the jet source, but not every arc points back in the same direction. For example, there is an interesting outcrop feature (to the upper right of the main outflow) that could be another random superposition of another outflow related to the slow precession of the intermittent jet source. Alternatively, this feature could be the result of the main outflow breaking apart.
The galaxy that happens to appear at the tip of HH 49/50 is a much more distant, face-on spiral galaxy. It has a prominent central bulge, shown in blue, which indicates the location of older stars. The bulge also shows signs of “side lobes”, suggesting that this may be a barred spiral galaxy. Reddish clumps within the spiral arms show the locations of warm dust and groups of forming stars. The galaxy even shows evacuated bubbles in these dusty regions, similar to nearby galaxies observed by Webb as part of the PHANGS program.
Webb captured these two unassociated objects in a lucky alignment. Over thousands of years, the edge of HH 49/50 will move outward and eventually appear to obscure the distant galaxy.
