Israeli researchers have made an exciting discovery: they measured cosmic rays, tiny invisible particles, deep within a dust cloud about 400 light-years from Earth. This groundbreaking study could change how we understand star formation in our galaxy.
Lead researcher Prof. Shmuel Bialy from the Technion-Israel Institute of Technology shared, “These cosmic rays are vital for understanding how new stars form. This research opens up a whole new area in astrophysics.” His team used the James Webb Space Telescope, a tool that can observe infrared radiation from cosmic rays embedded in the Barnard 68 nebula, located in the constellation Ophiuchus.
The findings were published in Nature Astronomy. Remarkably, Bialy’s team managed to detect signals that others believed were too faint to observe. “Nobody thought we could see these cosmic rays,” Bialy remarked. “Now, we have strong, clear evidence.”
Amit Chemke, a master’s student and co-author of the paper, explained the importance of this research: it helps us learn about star formation. “The Sun formed billions of years ago, but what about other suns?” he questioned.
So, what exactly are cosmic rays? Despite the confusing name, they aren’t rays of light. Victor F. Hess discovered them in 1912. Instead, they are high-energy particles made of protons, electrons, and atomic nuclei zipping through space at nearly light speed. When these particles collide with dust clouds, they can penetrate deeply, causing vibrations in hydrogen molecules. This vibration then emits infrared radiation, which astronomers can measure.
Nebulae are vast clouds of gas and dust that exist between stars, filled with elements like hydrogen and helium. Some nebulae are born from the leftovers of supernovae, while others are places where new stars form. Bialy described the size of these clouds: “The Sun is like a grain of salt compared to these giants.”
When cosmic rays hit a nebula, they can set off chemical reactions that create molecules like water and ammonia. “Cosmic rays play a role in star formation,” Chemke noted.
Before this discovery, researchers had primarily focused on infrared radiation from massive, hot stars, but detecting cosmic rays from nebulae was seen as nearly impossible. During the COVID-19 outbreak, Bialy continued to work on his theory about these cosmic rays. “Even if we never saw it, I enjoyed the calculations,” he said, reflecting on his passion for astronomy since childhood.
His journey led to collaboration with Italian astronomer Sirio Belli, and together they set up a telescope. Despite long hours of observation, their initial efforts didn’t yield results. But they didn’t give up. “Let’s try using NASA’s James Webb Space Telescope,” they thought. This telescope is much more sensitive than ground-based instruments.
After applying to NASA, they received a rare approval for eight hours of research time on the telescope. With its help, they observed the Barnard 68 nebula, which is cold and dense, and predicted to collapse into a star in about 200,000 years.
David Neufeld, a professor at Johns Hopkins University who also participated in the study, remarked that this research has opened new avenues in cosmic-ray astrophysics. The team has recently secured an additional 50 hours of observation time to gather more data, which will allow them to measure cosmic rays in more locations across the galaxy.
The studies not only give insight into stellar formation but also enhance our understanding of the universe around us. This discovery might not only deepen our grasp of star formation but could also lead to further groundbreaking research in astrophysics.
