A cosmic explosion in 2022 was the brightest ever — and may overturn decades-long theory on gamma ray bursts

Source: The post is based on the article “A cosmic explosion in 2022 was the brightest ever — and may overturn decades-long theory on gamma ray bursts” published in Down To Earth on 3rd April 2023

What is the News?

In 2022, Astronomers recorded the brightest gamma-ray radiation (named GRB 221009A) of all time, which could overturn a long-standing theory of GRB jets.

What are Gamma-ray bursts(GRB)?

Gamma-ray bursts are the strongest and brightest explosions in the universe, thought to be generated during the formation of black holes. 

Though they last mere seconds, gamma-ray bursts produce as much energy as the sun will emit during its entire 10-billion-year existence. 

GRBs were first seen in 1967 by the U.S. Air Force satellite called Vela. 

Types of GRBs: 

Long-duration gamma-ray bursts (LGRBs): LGRBs last for more than two seconds and are thought to be caused by the collapse of massive stars, known as supernovae.

– These explosions release a tremendous amount of energy and create a black hole at their center.

– LGRBs are the most common type of GRB and can be observed from distant galaxies.

Short-duration gamma-ray bursts (SGRBs): SGRBs last for less than two seconds and are thought to be caused by the collision of two compact objects, such as neutron stars or a neutron star and a black hole.

– SGRBs are much rarer than LGRBs, are more difficult to observe and typically located closer to our galaxy.

What is GRB 221009A?

GRB 221009A was a bright and long-lasting gamma-ray burst (GRB) jointly discovered by the Neil Gehrels Swift Observatory and the Fermi Gamma-ray Space Telescope.

GRB 221009A is only expected to happen once in many thousands of years. It may even be the brightest gamma-ray burst since human civilization began. Astronomers therefore dubbed it BOAT – the brightest of all time.

The burst was so bright it effectively blinded most gamma-ray instruments in space, which means they could not directly record the real intensity of the emission.

GRB 221009A is also the only seventh gamma-ray burst to display X-ray rings, and it triples the number previously seen around one.