What is a gamma-ray burst?
At least once a day, the sky lights up with a spectacular flash of gamma-rays coming from deep space. The brightness of this flash of gamma-rays can temporarily overwhelm all other gamma-ray sources in the universe. The burst can last from a fraction of a second to over a thousand seconds. The time that the burst occurs and the direction from which it will come cannot be predicted. Gamma-ray bursts (GRBs) can release more energy in 10 seconds than the Sun will emit in its entire 10 billion-year lifetime! In order to understand what a gamma-ray burst is, you must recognize gamma-rays as the most energetic form of light. Light, or electromagnetic radiation, can be thought of as coming in tiny packets of energy called photons. These photons come with a wide range of energies. At the low-energy end, we find radio waves. At the high-energy end, we find gamma-rays. The human eye is blind to nearly the entire electromagnetic spectrum, except for the very narrow range light that falls in what
