Astronomers have discovered a mysterious energetic burst from 8 billion years ago

FRBs are so powerful that even after traveling billions of light-years, only around 50 have been traced back to their host galaxies.

Key Takeaways

1. Astronomers have detected a fast radio burst (FRB) originating from a merger of galaxies dating back 8 billion years ago, the oldest known such burst.
2. This FRB released an immense amount of energy in less than a millisecond, roughly equivalent to the energy our sun emits over 30 years.
3. Using advanced telescopes like the Australian SKA Pathfinder and the European Southern Observatory’s Very Large Telescope, researchers pinpointed the FRB’s origin.
4. Hyper-magnetized neutron stars, known as magnetars, are the most likely sources of these extreme bursts, as they produce intense bursts solely in radio waves.
5. Fast radio bursts (FRBs) occur far more frequently than previously thought, with upwards of 100,000 believed to happen daily in the universe.

_________

The Discovery of Ancient FRB

Astronomers have identified a mysterious fast radio burst (FRB) originating from a merger of galaxies dating back 8 billion years. This discovery marks the oldest-known instance of such a burst, far surpassing previous records of 5 billion years. With the universe estimated to be about 13.8 billion years old, this finding offers a glimpse into the universe’s distant past.

FRBs are short-lived pulses of radio-frequency electromagnetic radiation that can outshine most other sources of radio waves in the universe. In less than a millisecond, this burst released the energy equivalent to what our sun emits over 30 years. This unprecedented event was detected using the Australian SKA Pathfinder, a state-of-the-art radio telescope, while its origin was pinpointed by the European Southern Observatory’s Very Large Telescope in Chile.

The Role of Magnetars in FRBs

The most likely source of these powerful FRBs is a hyper-magnetized neutron star, called a magnetar. Magnetars are stellar remnants that, despite having the mass of the sun, are only the size of a small city. They represent some of the most extreme and dense objects in the universe, making them capable of producing such intense bursts.

FRBs are unique because they emit energy solely in radio waves, with no observable emissions in other wavelengths such as optical light or X-rays. This distinct characteristic, combined with their brief duration, sets them apart from other energetic cosmic events like stellar explosions or black hole activity.

Until recently, FRBs were considered rare events, with only a handful traced back to their origin. However, new research suggests that FRBs may occur much more frequently than previously thought, with estimates suggesting upwards of 100,000 bursts occurring daily across the universe. Currently, only about 50 have been successfully traced back to their originating galaxies.

These bursts are crucial for understanding the vast intergalactic matter that exists between galaxies. As FRBs travel through space, they interact with the diffuse cosmic web of gas, some of which is so hot that it exists as ionized plasma. By studying these interactions, astronomers can gain valuable insights into the distribution and nature of this intergalactic matter—previously considered “missing” due to its diffuse and nearly invisible nature.

The discovery of an 8 billion-year-old FRB highlights not only the immense power of these cosmic events but also opens new avenues for understanding the evolution of the universe and the extreme environments that give rise to them.

The study published this week in the journal Science.