Earth sees the brightest radio bursts ever
Thousands of mysterious bursts of radio energy fill space every day; these huge flashes typically pack as much energy into a few milliseconds as the sun emits in all wavelengths in half a day.
Nobody knows what causes these fast radio bursts (FRBs), but theories include such dramatic possibilities as colliding neutron stars or neutron stars being eaten by black holes. A team of astronomers have witnessed the brightest such flash to date.
It was so bright that the scientists observed how the signal was altered by the intergalactic medium through which it traveled, much as starlight’s passage through Earth’s atmosphere makes stars twinkle.
Based on how the signal dispersed and distorted, the team confirmed that the signal had been traveling for at least a billion years, meaning its source was at least a billion light-years away.
The team also used the flash to determine properties of the tenuous plasmas between galaxies—such as magnetism and turbulence, confirming earlier theories that it is neither highly magnetized nor turbulent.
The scientists say that important as there are few other ways to study the galactic medium, which contains nearly 40% of all non-dark matter in the galaxy. But because FRBs occur without warning and don’t repeat, it’s unlikely that scientists will get a similar chance any time soon.
It was pure luck that the scientists that saw this neutron star in our own galaxy, by pointing its telescope in precisely the right direction.
More information: Science