"Suddenly, we saw in the distance a strong and intense flash of white light, which followed a descending and vertical trajectory and which broke up in six seconds, " the captain wrote.

CNN: Brazilian air force says debris was not from Air France crash

Its Burst Alert Telescope is set up to catch the intense but fleeting flash of very high-energy gamma radiation that initially signals a GRB event.

BBC: Observatory detects record burst

Foremost among these is what can create a flash so intense that it pours out more energy per second than billions of entire galaxies put together.

ECONOMIST: A symphony in gamma major