LID-568: A Rule-Breaking Black Hole Challenging Astrophysical Theories

LID-568: A Rule-Breaking Black Hole Challenging Astrophysical Theories

Sub : Sci

Sec: Space sector

Why in News

• An international team of researchers using NASA’s James Webb Space Telescope (JWST) and the Chandra X-ray Observatory has discovered a peculiar black hole, designated LID-568, which defies established astrophysical limits. This discovery offers valuable insights into the formation and rapid growth of supermassive black holes.

What is LID-568?

• LID-568 is a low-mass supermassive black hole that existed just 5 billion years after the Big Bang.
• It was discovered through the complementary observations of JWST and Chandra X-ray Observatory.
• This black hole was observed feeding on surrounding matter at nearly 40 times the previously established Eddington limit—a theoretical threshold for black hole accretion.
• This behaviour suggests a rapid growth mechanism previously thought improbable.
• LID-568 has surpassed this limit by a factor of 40, entering the category of super-Eddington accretion. Eddington Limit

About Eddington Limit:

• The Eddington limit, named after English astrophysicist Sir Arthur Eddington, represents the theoretical maximum luminosity a star or accretion disk can achieve when there is a balance between the outward radiation pressure and the inward gravitational force.
• At this limit, the radiation pressure counteracts gravity, preventing further accretion of matter.
• If an astronomical object exceeds the Eddington limit, the excessive luminosity would generate strong radiation pressure, potentially blowing off the outer layers of the star or accretion disk.
• This self-regulating mechanism ensures stability in the luminosity and mass of stars and accreting black holes.

About Super-Eddington Limit:

• When an object, such as a black hole, accretes matter at a rate surpassing the Eddington limit, it is said to be in a super-Eddington accretion phase.
• In this regime, the object emits luminosity greater than the Eddington luminosity, challenging traditional models of radiation pressure balance.
• Observations have identified black holes exhibiting super-Eddington accretion rates.
• For instance, the black hole LID-568, existing approximately 1.5 billion years after the Big Bang, was found to be consuming material at over 40 times the Eddington limit. Such findings provide insights into the rapid growth mechanisms of supermassive black holes in the early universe.

Black Holes:

• A black hole is a region in space where the gravitational pull is so intense that nothing, not even light, can escape from it. Black holes form from the remnants of massive stars that have ended their life cycles, collapsing under their own gravity.
• Event Horizon: The event horizon is the boundary surrounding a black hole beyond which no information or matter can return. It marks the point of no return; once an object crosses this threshold, it inevitably falls into the black hole.
• Singularity: At the core of a black hole lies the singularity, a point where matter is thought to be infinitely dense, and the gravitational pull is infinitely strong. In this region, the known laws of physics break down, and current theories cannot adequately describe the conditions.
• Accretion Disk: An accretion disk is a structure formed by diffused material in orbital motion around a central body, such as a black hole. In the context of black holes, the accretion disk consists of gas and dust spiraling inward, heating up due to friction and emitting radiation, often visible in X-rays.
• Spaghettification: Also known as the “noodle effect,” spaghettification refers to the process where objects are stretched and elongated as they approach a black hole due to extreme tidal forces. This occurs because the gravitational pull is significantly stronger on the side of the object closer to the black hole than on the far side.
• Supermassive black holes like Sagittarius A* at the Milky Way’s centre grow to millions or billions of times the Sun’s mass.
• Chandra X-ray Observatory: Initially identified LID-568 due to its exceptional brightness in X-rays, although it was invisible in optical and near-infrared wavelengths.