[Reading Science] The Ultra-Powerful 'Golden' Explosion That Shook the Entire Universe

NASA Releases Observation Images of GRB 211211A
Gamma-Ray Burst Caused by Neutron Star Collision
First Case with Initial Emission Lasting Over 1 Minute
"Creates Heavy Elements Like Gold Throughout the Universe"

The National Aeronautics and Space Administration (NASA) recently released images of an ultra-powerful gamma-ray burst (GRB), one of the greatest mysteries in space. The results contain new phenomena that overturn existing theories related to gamma-ray bursts, attracting significant attention.

On the 3rd (local time), NASA released images of the gamma-ray burst phenomenon (gamma-ray bursts·GRBs), specifically 'GRB 211211A', observed on December 11, 2021, by the Neil Gehrels Swift Observatory and the Fermi Gamma-ray Space Telescope. This event occurred in the outskirts of a galaxy in the constellation Bo?tes, approximately one billion light-years from Earth.

Scientists have long proposed two main causes for GRBs. When the initial emission lasts longer than 2 seconds, it is caused by the collapse of a massive star, forming a high-density celestial object such as a black hole at its core. Conversely, short gamma-ray emissions lasting less than 2 seconds are believed to result from the collision and merger of high-density celestial objects like neutron stars. This process is also accompanied by a phenomenon called a kilonova, where gamma rays are observed alongside infrared and visible light for a brief moment.

However, GRB 211211A broke this paradigm. Although it is presumed to be caused by a neutron star collision due to the accompanying kilonova phenomenon, the initial high-energy gamma-ray emission lasted an astonishing 1 minute. In other words, this was the first-ever case where an initial gamma-ray emission lasting more than 2 seconds was observed from a neutron star collision. Additional observations also detected the kilonova phenomenon, with an enormous amount of afterglow detected. According to observations from the Fermi Gamma-ray Space Telescope, high-energy gamma rays were detected for about 2 hours starting 1 hour and 30 minutes after the gamma-ray burst, with energy levels reaching 1 billion volts. Considering that the energy of visible light is only about 2 to 3 volts, this is an unimaginable figure.

Scientists regard such stellar collisions as a major source of heavy elements in the universe, such as gold. NASA explained, "Gamma-ray bursts, the most powerful events in the entire universe, occur when massive stars collapse under their own gravity to form black holes or when heavy neutron stars collide to form black holes, producing heavy materials like gold throughout the cosmos."

Meanwhile, the most powerful gamma-ray burst ever recorded was 'GRB 221009A', observed on October 9 last year. In March, a research team from Louisiana State University presented a paper at the American Astronomical Society stating that 'GRB 221009A' occurred about 1.9 billion light-years away and was the brightest and most powerful ever observed, occurring roughly once every 10,000 years. It was 70 times brighter than previous bursts. Since the initial emission lasted less than 2 seconds, it is believed to have originated from a black hole formed by the collapse of the core of a massive star under its own gravity.