In a groundbreaking discovery, astronomers have observed the birth of a solar system beyond our own for the first time, marking a significant milestone in the study of planetary formation.
An international team of researchers utilized data captured by the ALMA telescope in Chile along with the James Webb Space Telescope to pinpoint the exact moment when planets started to form around a star.
Their study, published in *Nature*, details the observations of hot minerals that are just beginning to solidify, representing the first specks of planet-forming material.
According to the paper, a gaseous disk surrounding the young star indicates the initial stages of the assembly process of a new planetary system.
Melissa McClure, a professor at Leiden University in the Netherlands and the study’s lead author, emphasized the importance of this finding in a statement issued by the European Southern Observatory (ESO).
“For the first time, we have identified the earliest moment when planet formation is initiated around a star other than our Sun,” she said.
Astronomers theorize that planets and small celestial bodies similar to those in our solar system likely formed through the mixture of interstellar solids with rocky materials that condense from the hot gases surrounding a nascent star.
However, the specific mechanisms behind the formation of our own solar system remain ambiguous.
Interestingly, the earliest solid material to condense near Earth’s location, orbiting the sun, has been found trapped in ancient meteorites, as noted by the ESO.
Over time, these newly condensed solids combine to initiate the planet formation process as they increase in size and mass.
In their research, astronomers found compelling evidence that the hot minerals began to condense in the disk surrounding a protostar named HOPS-315.
“This process has never been seen before in a protoplanetary disc—or anywhere outside our solar system,” remarked Edwin Bergin, an astronomer at the University of Michigan and a co-author of the paper.
The HOPS-315 protostar is situated in the Orion B molecular cloud, approximately 1,300 light-years away from Earth, and is uniquely oriented to provide a direct view of its inner gaseous disk.
This direct view is rare due to the jets of gas emitted by protostars, known as outflow, which usually obstruct visibility of the disk.
Utilizing infrared and millimeter wavelengths from both ground and space telescopes, astronomers were able to detect solids beginning to condense from the cooling gas—a significant moment known as “time zero” for planet formation.
The James Webb Space Telescope, recognized as the most powerful telescope ever launched, was instrumental in probing the chemical composition around the protostar.
It detected crystalline silicate materials, which are considered “telltale signs” of early planet formation, according to the paper.
Remarkably, the chemical signals are believed to originate from a small region of the disk corresponding to the orbit of the asteroid belt in our own solar system.
“This hot mineral is the first feedstock that you have to start growing things in the dark,” McClure explained.
This discovery represents the first time a planetary system has been identified at such an early stage.
Although astronomers have previously identified young disks containing massive newborn planets similar to Jupiter, they had not confirmed that the first solid components, known as planetesimals, must form earlier in the timeline of planetary formation.
The finding provides insights into the past of our solar system, raising the possibility that the formation processes of the new system closely mirror the conditions present at the dawn of Earth’s own planetary system.
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