Astronomers used the Atacama Large Millimeter/Submillimeter Array (ALMA) to take high-resolution images of eight protoplanetary disks. sigma orionisa star cluster that is irradiated with strong ultraviolet light from a massive star. Surprisingly, they found evidence of gaps and rings in most of the disks. These are the substructures commonly associated with the formation of giant exoplanets.
These ALMA images show the rich disk structure around the star Sigma Orioni. Image credits: ALMA / ESO / JAO / National Astronomical Observatory of Japan / NRAO / Huang others.
“We expected that high levels of radiation within this cluster would inhibit planet formation in the outer regions of these disks,” the Columbia University astronomers said. jane fan.
“But instead, we are seeing signs that planets may be forming at distances of tens of astronomical units from their stars, similar to what we have observed in less harsh environments.”
Previous research has focused on regions of the disk with little ultraviolet (UV) radiation.
This study used ALMA's highest resolution to observe a disk in a much harsher environment.
“These observations suggest that the processes driving planet formation are very robust and can function even under difficult conditions,” said Dr. Huang.
“This gives us even more confidence that planets may be forming in many more places across the galaxy, even in areas previously thought to be too harsh.”
The discovery has important implications for understanding the formation of our own solar system, which likely evolved in a similar high-radiation environment.
These also motivate future studies of disks in more extreme stellar neighborhoods.
Astronomers used ALMA's most extended antenna configuration to obtain unprecedented detail in disk images, achieving a resolution of about 8 AU (astronomical units).
This allowed us to resolve several different gaps and rings on several disks.
The exact nature of these disk structures is still under debate, but it is thought that they either contribute to planet formation or are the result of interactions between the forming planet and the disk's material.
“Our observations suggest that the substructure is common not only in disks near mildly illuminated star-forming regions, but also in disks exposed to intermediate levels of external ultraviolet radiation.” the researchers said.
“If these substructures track planet-disk interactions, ice and gas giant planets may still be forming on Solar System scales in Sigma Orioni, but with very large semi-major axes (50 Giant planet formation in the ~100 AU) region may be rare compared to star formation in nearby regions. ”
“These observations motivate high-resolution imaging of the disk in more extreme ultraviolet environments to investigate the universality of the disk's substructure.”
of findings Coming up this week are: astrophysical journal.
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jane fan others. 2024. High-resolution ALMA observations of the highly structured protoplanetary disk of σ Orionis. APJ 976,132;doi: 10.3847/1538-4357/ad84df
Source: www.sci.news
