Israeli Researchers Detect Stellar-Creation Particles, Offering New Insights into Star Formation
In a significant advancement for astrophysics, researchers in Israel have successfully measured cosmic rays – high-energy particles – within a dust cloud located light-years from Earth. The findings, published in Nature Astronomy on , could unlock new understanding of the processes that govern star birth.
The research, led by Professor Shmuel Bialy of the Technion-Israel Institute of Technology’s Physics Faculty, centers on the detection of these previously unobservable particles. “These cosmic rays are crucial for our understanding of the process of formation of new stars,” Bialy told The Times of Israel. “This just opened the door for a whole new field of research in modern astrophysics.”
Unveiling the Invisible: How the Detection Was Achieved
The team utilized observations from NASA’s James Webb Space Telescope to measure infrared radiation emanating from cosmic rays that had penetrated Barnard 68, a massive nebula in the constellation Ophiuchus. This nebula, approximately two million times larger than the Sun, is a cold and dense region with temperatures hovering around 10-20 Kelvin – just above absolute zero – and is predicted to collapse and form a new star within roughly years.
Cosmic rays, despite their name, aren’t a form of radiation or light. Discovered by Victor F. Hess in , they are actually particles of matter – protons, electrons, and atomic nuclei – traveling at nearly the speed of light. These particles permeate the galaxy and, when they collide with dust clouds like Barnard 68, they cause hydrogen molecules within the nebula to vibrate, emitting infrared radiation that the James Webb Space Telescope was able to detect.
The Role of Cosmic Rays in Star Formation
Amit Chemke, a master’s student in Bialy’s group and co-author of the research, explained the significance of this interaction. “The cosmic rays have an effect on the star formation process,” Chemke said. The collision of cosmic rays with nebulae also sparks chemical processes, leading to the creation of molecules like water, ammonia, and methanol.
Nebulae themselves are vast clouds of gas and dust existing between stars. They can originate from the remnants of dying stars or serve as the birthplaces of new ones. Bialy emphasized the scale of these structures, stating, “The Sun is like a grain of salt compared to these clouds.”
A Long-Held Theory Finally Confirmed
The ability to observe these cosmic rays was previously considered impossible due to their faint signal. Scientists believed the radiation emitted would be too weak to detect. However, Bialy’s decades-long theory, coupled with the enhanced capabilities of the James Webb Space Telescope, proved otherwise. “Nobody thought it would be possible to observe these cosmic rays because they were never seen before,” Bialy stated. “Now, we show that it’s possible. We were the first to observe it, and the signal was strong and clear.”
The research began during the COVID-19 pandemic, with Bialy continuing his calculations despite skepticism from the scientific community. He shared his findings with Italian astronomer Sirio Belli, who specializes in infrared radiation observation. Initial attempts using a ground-based telescope in Arizona proved unsuccessful, prompting them to apply for research time on the James Webb Space Telescope.
Securing observation time on the telescope is highly competitive, with only one in ten proposals being approved. After several attempts, Bialy’s team was granted eight hours of research time. The resulting data confirmed their predictions and opened a new avenue for studying cosmic-ray astrophysics.
Looking Ahead: Mapping Cosmic Rays Across the Galaxy
The team has already been awarded an additional hours of observational data from the James Webb Space Telescope. Bialy plans to use this time to measure the intensity of cosmic rays in numerous locations throughout the galaxy, ultimately aiming to create a comprehensive map of their distribution. “And in the years to come, we plan to extend it even further, maybe to many tens of nebulae around us to measure the distribution of cosmic rays throughout galactic space,” he said.
Johns Hopkins University professor David Neufeld, also involved in the study, noted that the data from the James Webb Space Telescope “has opened a completely new window on cosmic-ray astrophysics.” This breakthrough promises to reshape our understanding of the fundamental processes that drive star formation and the evolution of galaxies.
