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NASA’s Webb Snaps Supersonic Outflow of Young Star

At the center is a thin horizontal pinkish cloud known as Herbig-Haro 211 that is uneven with rounded ends, and tilted from bottom left to top right. It takes up about two-thirds of the length of this angle, but is thinner and longer at the opposite angle. At its center is a dark spot. On either side of the dark spot, there are orangish yellow wisps that extend to light blue wisps. Within the center of those clouds, a pink fluffy streak runs through each lobe. At the ends of each lobe, pink becomes the dominant color. The lobe to the left is fatter. The right lobe is thinner, and ends in a smaller pink semi-circle. Just off the edge of this lobe is a slightly smaller pink semicircle, then a pink sponge-like blog. The background contains several bright stars, each with eight diffraction spikes extending out from the central bright point.
NASA’s James Webb Space Telescope’s high resolution, near-infrared look at Herbig-Haro 211 reveals exquisite detail of the outflow of a young star, an infantile analogue of our Sun. Herbig-Haro objects are formed when stellar winds or jets of gas spewing from newborn stars form shock waves colliding with nearby gas and dust at high speeds. The image showcases a series of bow shocks to the southeast (lower-left) and northwest (upper-right) as well as the narrow bipolar jet that powers them in unprecedented detail. Molecules excited by the turbulent conditions, including molecular hydrogen, carbon monoxide and silicon monoxide, emit infrared light, collected by Webb, that map out the structure of the outflows.
ESA/Webb, NASA, CSA, T. Ray (Dublin Institute for Advanced Studies)

Herbig-Haro (HH) objects are luminous regions surrounding newborn stars, formed when stellar winds or jets of gas spewing from these newborn stars form shock waves colliding with nearby gas and dust at high speeds. This image of HH 211 from NASA’s James Webb Space Telescope reveals an outflow from a Class 0 protostar, an infantile analog of our Sun when it was no more than a few tens of thousands of years old and with a mass only 8% of the present-day Sun (it will eventually grow into a star like the Sun).

Infrared imaging is powerful in studying newborn stars and their outflows, because such stars are invariably still embedded within the gas from the molecular cloud in which they formed. The infrared emission of the star’s outflows penetrates the obscuring gas and dust, making a Herbig-Haro object like HH 211 ideal for observation with Webb’s sensitive infrared instruments. Molecules excited by the turbulent conditions, including molecular hydrogen, carbon monoxide, and silicon monoxide, emit infrared light that Webb can collect to map out the structure of the outflows.

The image showcases a series of bow shocks to the southeast (lower-left) and northwest (upper-right) as well as the narrow bipolar jet that powers them. Webb reveals this scene in unprecedented detail — roughly 5 to 10 times higher spatial resolution than any previous images of HH 211. The inner jet is seen to “wiggle” with mirror symmetry on either side of the central protostar. This is in agreement with observations on smaller scales and suggests that the protostar may in fact be an unresolved binary star.

Earlier observations of HH 211 with ground-based telescopes revealed giant bow shocks moving away from us (northwest) and moving towards us (southeast) and cavity-like structures in shocked hydrogen and carbon monoxide respectively, as well as a knotty and wiggling bipolar jet in silicon monoxide. Researchers have used Webb’s new observations to determine that the object’s outflow is relatively slow in comparison to more evolved protostars with similar types of outflows.

The team measured the velocities of the innermost outflow structures to be roughly 48-60 miles per second (80 to 100 kilometers per second). However, the difference in velocity between these sections of the outflow and the leading material they’re colliding with — the shockwave — is much smaller. The researchers concluded that outflows from the youngest stars, like that in the center of HH 211, are mostly made up of molecules, because the comparatively low shock wave velocities are not energetic enough to break the molecules apart into simpler atoms and ions.

The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

Media Contacts:

Laura Betz
NASA’s Goddard Space Flight Center, Greenbelt, Md.
laura.e.betz@nasa.gov

Hannah Braun
Space Telescope Science Institute, Baltimore, Md.
hbraun@stsci.edu

Bethany Downer
ESA/Webb Chief Science Communications Officer
Bethany.Downer@esawebb.org