Astronomers using the NASA/ESA/CSA James Webb Space Telescope have captured a new image of Herbig-Haro (HH) 46/47, a tightly bound pair of actively forming stars located in the constellation of Vela.
This Webb image shows a pair of actively forming stars, known as Herbig-Haro 46/47, in high-resolution near-infrared light. To find them, trace the bright pink and red diffraction spikes until you hit the center. The stars are within the orange-white splotch. They are buried deeply in a disk of gas and dust that feeds their growth as they continue to gain mass. The disk is not visible, but its shadow can be seen in the two dark, conical regions surrounding the central stars. Image credit: NASA / ESA / CSA / Joseph DePasquale, STScI.
Herbig-Haro objects are small bright patches of nebulosity associated with newborn stars.
They are formed when hot gas ejected by a newborn star collides with the gas and dust around it at speeds of up to 250,000 kmh (155,000 mph), creating bright shock waves.
These objects come in a wide array of shapes, the basic configuration is usually the same: twin jets of heated gas, ejected in opposite directions from a forming star, stream through interstellar space.
Herbig-Haro objects are transient phenomena — they disappear into nothingness within a few tens of thousands of years.
These objects were first observed in the 19th century by the American astronomer Sherburne Wesley Burnham, but were not recognized as being a distinct type of emission nebula until the 1940s.
The first astronomers to study them in detail were George Herbig and Guillermo Haro, after whom they have been named.
The pair of such objects, HH 46/47, resides approximately 1,470 light-years away from Earth in the constellation of Vela.
“The most striking details are the two-sided lobes that fan out from the actively forming central stars, represented in fiery orange,” Webb astronomers said.
“Much of this material was shot out from those stars as they repeatedly ingest and eject the gas and dust that immediately surround them over thousands of years.”
“When material from more recent ejections runs into older material, it changes the shape of these lobes.”
“This activity is like a large fountain being turned on and off in rapid, but random succession, leading to billowing patterns in the pool below it.”
“Some jets send out more material and others launch at faster speeds.”
“Why? It’s likely related to how much material fell onto the stars at a particular point in time,” they said.
“The stars’ more recent ejections appear in a thread-like blue. They run just below the red horizontal diffraction spike at 2 o’clock. Along the right side, these ejections make clearer wavy patterns.”
“They are disconnected at points, and end in a remarkable uneven light purple circle in the thickest orange area.”
“Lighter blue, curly lines also emerge on the left, near the central stars, but are sometimes overshadowed by the bright red diffraction spike.”
“All of these jets are crucial to star formation itself. Ejections regulate how much mass the stars ultimately gather.”
“Now, turn your eye to the second most prominent feature: the effervescent blue cloud.”
“This is a region of dense dust and gas, known both as a nebula and more formally as a Bok globule.”
“When viewed mainly in visible light, it appears almost completely black — only a few background stars peek through.”
“In Webb’s near-infrared image, we can see into and through the gauzy layers of this cloud, bringing a lot more of HH 46/47 into focus, while also revealing a deep range of stars and galaxies that lie well beyond it,” they said.
“The nebula’s edges appear in a soft orange outline, like a backward L along the right and bottom.”
“This nebula is significant — its presence influences the shapes of the jets shot out by the central stars.”
“As ejected material rams into the nebula on the lower left, there is more opportunity for the jets to interact with molecules within the nebula, causing them both to light up.”
“There are two other areas to look at to compare the asymmetry of the two lobes.”
“Glance toward the upper right to pick out a blobby, almost sponge-shaped ejecta that appears separate from the larger lobe.”
“Only a few threads of semi-transparent wisps of material point toward the larger lobe.”
“Almost transparent, tentacle-like shapes also appear to be drifting behind it, like streamers in a cosmic wind.”
“In contrast, at lower left, look beyond the hefty lobe to find an arc.”
“Both are made up of material that was pushed the farthest and possibly by earlier ejections.”
“The arcs appear to be pointed in different directions, and may have originated from different outflows.”
