Gamma-ray bursts are known to be the strongest and brightest explosions in the universe. Scientists believe that these ultrabright flashes are generated during the formation of black holes and that they emit energy as much as the Sun will emit in its 10-billion-year existence.

Earlier data on Gamma-ray bursts suggest that the source of Gamma-ray bursts could be somewhere in galaxies that are billions of light-years away from the Milky Way and that the source of bursts produces an afterglow that is less-energetic wavelengths.


 Gamma-Ray Bursts: What Do These Ultrabright Flashes Tell About the Universe?
(Photo: Wikimedia Commons)
This artist’s impression shows two galaxies in the early Universe. The brilliant explosion on the left is a gamma-ray burst. As the light from the burst passes through the two galaxies on the way to Earth (outside the frame to the right), some colors are absorbed by the cool gas in the galaxies, leaving characteristic dark lines in the spectrum. Careful study of these spectra has allowed astronomers to discover that these two galaxies are remarkably rich in heavier chemical elements.

A Brief History of the Discovery of Gamma-Ray Bursts

The first Gamma-ray burst was discovered in July 1967 during the height of the Cold War. American satellites called Vela 3 and 4 were launched to look for Soviet nuclear weapons when they observed brief flashes of high-energy photons, also known as Gamma-rays.

The 1973 paper, titled "Observations of gamma-ray bursts of cosmic origin," published in the Astrophysical Journal, compiled over a dozen of Gamma-ray bursts. Since then, scientists have been trying to understand these bright explosions from space.

Astronomers debated where the bright beams were coming from and what force is powering them. Some believe that these powerful sources must be nearby in the solar system, while others argue that it lies in the cosmos beyond.

It was in 1997 when the Italian and Dutch satellite called BeppoSAX confirmed that Gamma-ray bursts are from other galaxies, with some of them originating from billions of light-years away.

These findings were baffled, and scientists believe that the only explanation could be that these ultrabright beams must be extremely powerful. "We thought there was no way you could get that amount of energy in an explosion from any object in the universe," Wired quoted astrophysicist Sylvia Zhu.

According to Wired, Gamma-ray bursts could emit energy as much as the energy produced in a supernova when a star collapses and explodes. But instead, for weeks, it could create the strong and brightest explosions in the universe in just a few seconds or minutes. Their luminosities could peak at 100 billion times than the Sun and a billion times than the brightest supernovas.

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Two Types of Gamma-Ray Bursts

When astronomers observed how long Gamma-ray bursts lasted, they noticed that there are two types of bursts, according to NASA. These are the long-duration and short-duration Gamma-ray bursts. Scientists said that these types are likely created by different processes, but both result in a brand new black hole.

Long-duration Gamma-ray bursts could last from 2 seconds to a few hundred seconds or several minutes, with an average time of 30 seconds. This type is associated with massive star deaths, although scientists noted that not all supernovas generate Gamma-ray bursts.

On the other hand, short-duration bursts last between a few milliseconds to 2 seconds, with an average time of 0.3 seconds or 300 milliseconds. They are associated with the merger of a neutron star and a new black hole or a neutron star with a black hole that is from a larger black hole.

Scientists said that these bursts and their afterglows could give insights into the universe. These bursts give a window into the wreckage of supernovas and star mergers in which scientists could use to track how the chemical composition of the universe has changed over time.

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