Using Near-infrared camera (nircam) Mid-infrared instrument (Mil)Advanced on a James Webbspace Telescope, astronomers took a stunning image of an edge-on-protoplanetary disc around a Herbig Halo object HH 30The Dark Cloud LDN 1551, is located in Taurus Molecular Cloud.
The Herbig-Haro object is a small bright patch of nebula associated with protostars in the star-forming region.
These structures were first observed in the 19th century by American astronomer Sherburn Wesley Burnham, but were not recognized as a distinct type of ejection nebula until the 1940s.
The first astronomers to study them in detail were George Harbigue and Guillermo Halo, and they were later named.
Herbig Halo objects are formed in very specific circumstances. Hot gas discharged by the newborn star collides with the gas, hitting it at a speed of up to 250,000 kmh (155,000 mph), creating a bright shock wave.
They come in a wide range of shapes. The basic configuration is usually the same. Twin jets of hot gases are ejected in the opposite direction from the forming stars and flow through interstellar space.
“HH 30 is an example of where this effluent gas takes the form of a narrow jet,” the astronomer said.
“The source star is on one end of the jet and is hidden behind an edge-on-protoplanetary disc illuminated by the star.”
Using Webb Instruments, researchers investigate HH 30 objects in great detail.
They also analyzed data from the NASA/ESA Hubble Space Telescope and Atacama's Large Millimeter/Sub-Millimeter Array (ALMA).
“Long-wavelength data from Alma tracks the location of millimeter-sized dust particles in a narrow area on the middle surface of the disk,” they said.
“Short wavelength infrared data from Webb reveals the distribution of smaller dust grains.”
“These grains are one millionth of a meter in diameter. They are the size of a single bacteria.”
“Large dust grains are concentrated in the most dense portions of the disc, while small grains are much more widely used.”
“Combined with Alma's sharp radio-wavelength eyes, Webb's observations show that large dust particles must migrate within the disk and precipitate into a thin layer,” they added.
“Creating narrow, dense layers of dust is an important step in the formation of the planet.”
“In this densely populated area, dust grains together form pebbles, and ultimately form the planet itself.”
“In addition to the behavior of dust grains, images of Webb, Hubble and Alma reveal several different structures nested with each other.”
“A high-speed jet of gas appears at a 90-degree angle from the narrow central disc.”
“The narrow jet is surrounded by wider, cone-shaped spills.”
“Enclosing the cone runoff is a broad nebula that reflects the light from the young stars embedded in the disc.”
“Together, these data reveal that HH 30 is a dynamic location, where small dust grains and huge jets play a role in the formation of a new planet.”
Survey results It will be published in Astrophysical Journal.
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Ryozaki et al. 2025. JWST imaging of edge-on protranetary discs. IV. HH 30 disc mid-infrared dust scattering. APJin press; Arxiv: 2412.07523
Source: www.sci.news
