A study has discovered particles that potentially existed before the sun, aiding our understanding of how the solar system formed.
The study, which was published Monday, found microscopic, glasslike grains inside dust in the Earth’s upper atmosphere left over from the solar system before it was formed. The team of scientists who authored the study, which included researchers from Lawrence Berkeley National Laboratory, believes the dust came from comets.
“What it suggests is that we have a lot more pre-solar material that has survived in our solar system than scientists have been assuming,” said University of Hawaii at Manoa researcher Hope Ishii, who led the study.
According to the study, most of the dust was destroyed and remade by natural processes, leading to planet formation. The surviving dust particles usually are preserved in comets, according to a press release from Berkeley Lab on the findings.
The glassy grains inside the dust are called GEMS, or glass embedded with metal and sulfides, and they are smaller than one-hundredth of the thickness of a strand of human hair, according to the press release.
When asked if the particles can give insight into what the solar system was like before the sun existed, Ishii said, “That might be ambitious, but we can learn a lot more about how solar systems form from work like this.”
The particles were surrounded by large amounts of organic carbon, which Ishii said preserved the particles “well” during their 4.6 million years of existence. The carbon is very sensitive to heat, so it must have formed in a “a cold, radiation-rich environment, such as the outer solar nebula or pre-solar molecular cloud,” according to the press release.
The scientists made the discovery using tools such as ion and electron microscopes. Since the particles were so small, the electron microscope allowed the researchers to obtain images of the GEMS by probing their samples with electrons, Ishii said.
Some of the research took place at Berkeley Lab in order to study particles’ chemical composition using infrared light at the lab’s Advanced Light Source, or ALS, which confirmed the presence of organic carbon, identifying the coupling of carbon with nitrogen and oxygen. The ALS is a particle accelerator that uses X-rays for research.
“The work that was done by electron microscopy at LBL was a beautiful study,” said UC Berkeley researcher Andrew Westphal. “In terms of the conclusion, I have some hesitation.”
About three weeks ago, Westphal and his team submitted a paper to the Astrophysical Journal that concluded the opposite of Ishii’s study. Specifically, it claims that the particles are not part of the “interstellar silicates in the interstellar medium,” according to Westphal.
Westphal acknowledged that the new study is compelling, especially in its methodology, but he is still hesitant to accept its conclusion as fact.
Westphal’s study used different equipment than Ishii’s study, including an X-ray microprobe and direct observations from NASA’s Chandra X-ray Observatory.
“Different conclusions using different techniques — that is telling you something interesting,” Westphal said.
A previous version of this article may have implied that Lawrence Berkeley National Laboratory belongs to UC Berkeley. In fact, it is a U.S. federal government national laboratory managed by the UC system.