Black hole

What is a black hole?

• A black hole is an object in space that is so dense and has such strong gravity that no matter or light can escape its pull. Because no light can escape, it is black and invisible.

What is Event Horizon?

• There’s a boundary at the edge of a black hole called the event horizon, which is the point of no return — any light or matter that crosses that boundary is sucked into the black hole.
• It would need to travel faster than the speed of light to escape, which is impossible.

What is Singularity?

• Anything that crosses the event horizon is destined to fall to the very centre of the black hole and be squished into a single point with infinite density, called the singularity.

If black holes are invisible, how can we detect or photograph them?

1. By looking for the effects of their extreme gravity, which pulls stars and gases toward them.
2. Also, while anything past the event horizon is invisible, outside that boundary there is sometimes a spiral disk of gas that the black hole has pulled toward — but not yet into — itself.
3. The gases in that accretion disk are heated up as they accelerate toward the black hole, causing them to glow extremely brightly. The colours they glow are invisible to us, but are detectable with an X-ray telescope.
4. Scientists have also detected the gravitational waves generated when two black holes collide. light surrounding the black hole right to the edge of the event horizon, which is the goal of the Event Horizon Telescope.

How big are black holes?

• Small black holes are called stellar-mass black holes. They have masses similar to those of larger stars — about five to 20 times the mass of the sun.
• The other kind is supermassive black holes, which are millions to billions of times more massive than the sun. That’s the kind the Event Horizon Telescope has been trying to photograph, as bigger objects ought to be easier to see. There is some evidence that black holes between these two sizes exist, but that has yet to be confirmed.
• While black holes are very massive, that doesn’t mean they take up a lot of space. Because they’re so dense, they’re actually quite small. According to NASA, a black hole 20 times the mass of the sun could fit inside a ball 16 kilometres wide — the width of the Island of Montreal at its widest point.

Intermediate mass Black Holes

• Using data from the Hubble Space Telescope and two X-ray observatories, the researchers determined that this black hole is more than 50,000 times the mass of our sun and located 740 million light years from Earth in a dwarf galaxy, one containing far fewer stars than our Milky Way.
• Black holes are extraordinarily dense objects possessing gravitational pulls so powerful that not even light can escape.
• This is one of the few “intermediate-mass” (PT SHOT) black holes ever identified, being far smaller than the supermassive black holes that reside at the center of large galaxies but far larger than so-called stellar-mass black holes formed by the collapse of massive individual stars. An object that was discovered originally back in 2010 is indeed an intermediate-mass black hole that ripped apart and swallowed a passing star
• The star was probably roughly a third the mass of the sun. Scientists have searched for intermediate-mass black holes for four decades and fewer than 10 good examples are known, though large numbers may exist.
• “So finding a new one is very significant. Also, a black hole swallowing a star happens on average only once every 10,000 years or so in any particular galaxy so these are rare occurrences,”
• The supermassive black hole at the centre of the Milky Way is 4 million times the mass of the sun and located 26,000 light years from Earth. The closest stellar-mass black star is about 6,000 light years from Earth. A light year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).
• Scientists called intermediate-mass black holes the “missing link” in understanding the range of black holes.

Where are black holes found?

• Supermassive black holes are found at the centre of most galaxies, including our own Milky Way. The one in our galaxy is called
• Sagittarius A* and is one of those the Event Horizon Telescope has been attempting to photograph.
• Sagittarius A* isn’t the only black hole in our galaxy, though.
• Earlier this year, astronomers discovered another 12 within three light-years of it, suggesting there could be upwards of 10,000 black holes around the galactic centre.

Where do black holes come from?

• Supermassive black holes are believed to form at the same time as the galaxy that surrounds them, but astronomers aren’t sure exactly how.
• Stellar mass black holes form when a star with a mass greater than three times that of our sun runs out of fuel. It explodes into a supernova and collapses into an extremely dense core that we know as a black hole — something predicted by Albert Einstein’s general theory of relativity.
• Einstein’s theory also predicts the size and shape of the black holes that the Event Horizon Telescope is trying to photograph.

What is a Blazar?

• Through 153 nights, 17 scientists from 9 countries in Europe and Asia including researchers from Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital (PT), an autonomous institution of the Department of Science and Technology (DST), Government of India took 2263 image frames and observed the changes in a very high energy gamma-ray emitting blazar ‘1ES 0806+524’ using seven optical telescopes in Europe and Asia.
• A blazar is a feeding super-massive black-hole (SMBH) in the heart of a distant galaxy that produces a high-energy jet viewed face-on from Earth. Blazars are one of the most luminous and energetic objects in the known universe with a jet composed of ionized matter traveling at nearly the speed of light directed very nearly towards an observer.
• Blazars are among one of the most favourite astronomical transient objects because they emit radiation in the complete electromagnetic (EM )spectrum, and their flux and polarization are highly variable.

Click here to read about all the other terminologies related to Black Hole and Universe.

FSDC (Financial Stability and Development Council)

• With a view to strengthening and institutionalizing the mechanism for maintaining financial stability, enhancing inter-regulatory coordination and promoting financial sector development, the Financial Stability and Development Council (FSDC) was set up by the Government as the apex level forum in December 2010.
• The Chairman of the FSDC is the Finance Minister and its members include the heads of financial sector Regulators (RBI, SEBI, PFRDA, IRDA & FMC) Finance Secretary and/or Secretary, Department of Economic Affairs, Secretary, Department of Financial Services, and Chief Economic Adviser.
• The Council can invite experts to its meeting if required.
• Without prejudice to the autonomy of regulators, the Council monitors macro-prudential supervision of the economy, including the functioning of large financial conglomerates, and addresses inter-regulatory coordination and financial sector development issues.
• It also focuses on financial literacy and financial inclusion.

What is Macroprudential policy?

• Macroprudential policy is a novel way of looking into financial regulation. It aims to prevent the build-up of risk (resulting from external factors and market failures); make the financial sector more resilient and limit contagion effects and create a perspective to create the right set of incentives.

What is Financial Stability?

• Monetary stability (say maintaining low and stable inflation) leads to financial stability. Monetary stability is an important precondition for financial stability. Contextually, financial stability in India means
  1. ensuring uninterrupted settlements of financial transactions (both internal and external),
  2. maintenance of a level of confidence in the financial system amongst all the participants and stakeholders and
  3. absence of excess volatility that unduly and adversely affects real economic activity.
• Forces affecting financial stability, include:
  1. boom in credit to private sector, both investment and consumption, A particular form of boom and bust cycle is generated by the end of hyperinflation episodes.
  2. highly regulated systems have also suffered crises.
  3. Direct effects of fiscal difficulties and crisis in one country has a direct effect on economic conditions.
  4. Terms of trade shocks and movements in real exchange rates.
  5. Political instability, unrest, civil conflict.
  6. Policy-induced distortions, government influence over public sector banks.

About Financial Stability and Development Council (FSDC)

• The idea to create such a super regulatory body was first mooted by the Raghuram Rajan Committee in 2008.
• Finally in 2010, the then Finance Minister of India, Pranab Mukherjee, decided to set up such an autonomous body dealing with macro-prudential and financial regularities in the entire financial sector of India.
• It was set up as a non-statutory organisation in 2010. To maintain financial stability and enhance inter-regulatory coordination.
• The Chairman of the FSDC is the Finance Minister and its members include the heads of the financial sector regulatory authorities (i.e, SEBI, IRDA, RBI, PFRDA and FMC) , Finance Secretaries and the Chief Economic Adviser.
• FMC was added in 2013. FSDC would monitor macro-prudential supervision of the economy, including the functioning of large financial conglomerates.
• It will address inter-regulatory coordination issues.
• It will also focus on financial literacy and financial inclusion. Prior to FSDC, it was an objective of monetary policy.
• The recent global economic meltdown has put pressure on governments and institutions across the globe to regulate their economic assets.
• This council is seen as India's initiative to be better conditioned to prevent such incidents in future.
• The new body envisages to strengthen and institutionalise the mechanism of maintaining financial stability, financial sector development, inter-regulatory coordination along with monitoring macro-prudential regulation' of economy.
• No funds are separately allocated to the council for undertaking its activities.

Composition of FSDC

• Chairperson: The Union Finance Minister of India
• Governor Reserve Bank of India (RBl),
• Finance Secretary and/ or Secretary, Department of Economic Affairs (DEA),
• Secretary, Department of Financial Services (DFS),
• Secretary, Ministry of Corporate Affairs,
• Secretary, Ministry of Electronics and Information Technology,
• Chief Economic Advisor, Ministry of Finance,
• Chairman, Securities and Exchange Board of India (SEBI),
• Chairman, Insurance Regulatory and Development Authority (IRDA),
• Chairman, Pension Fund Regulatory and Development Authority (PFRDA),
• Chairman, Insolvency and Bankruptcy Board of India (IBBI),
• Additional Secretary, Ministry of Finance, DEA, will be the Secretary of the Council,
• The Chairperson may invite any person whose presence is deemed necessary for any of its meetings.

Responsibilities

• Financial Stability
• Financial Sector Development
• Inter-Regulatory Coordination
• Financial Literacy
• Financial Inclusion
• Macro prudential supervision of the economy including the functioning of large financial conglomerates.
• Coordinating India's international interface with financial sector bodies like the Financial Action Task Force (FATF), Financial Stability Board (FSB) and any such body as may be decided by the Finance Minister from time to time.

The institutional structure for India’s Financial Inclusion/ Literacy programme is unique as it has an apex body in the Financial Stability and Development Council (FSDC), headed by the Finance Minister of Government of India, mandated, inter alia, to focus on attaining financial inclusion/ literacy goals.

Structural and Functional changes

• To Entrust it with the tasks of existing regulators i.e. RBI, IRDA, SEBI, PFRDA.
• The Council shall have a sub-committee headed by the Governor, RBl. The sub-committee will replace the existing High Level Coordination Committee on Financial Markets.
• Sectoral regulators’ autonomy to be protected.
• Guidelines prepared on functioning of the Financial Stability and Development Council (FSDC), a high-level body set up to sort out inter-regulatory issues, will define the role of the finance ministry and how member regulators’ autonomy is not compromised.
• FSDC was formed to bring greater coordination among financial market regulators. The council is headed by the finance minister and has the Reserve Bank of India (RBI) governor and chairpersons of the Securities and Exchange Board of India, Insurance Regulatory and Development Authority and Pension Fund Regulatory and Development Authority as other members along with finance ministry officials.
• RBI and other regulators had earlier feared that their autonomy was at stake as FSDC was headed by the finance minister herself. After the assurance of FM, this fear was set to rest but functional guidelines was supposed to address this issue.

Financial Sector Legislative Reforms Commission (FSLRC- 2013)

• Financial Sector Legislative Reforms Commission (FSLRC- 2013) had thoroughly redefined the role of FSDC. It recommended
  1. It recommended making FSDC a statutory body to perform the mandate of financial stability/ systemic risk management.
  2. It also suggested a data center called Financial Data Management Center (FDMC) to work with FSDC.

Financial Data Management Center (FDMC)

• Budget 2016-17 set up FDMC under FSDC to facilitate integrated data aggregation and analysis in financial sector.
• FSDC presently works in a two-tier structure.
• While FSDC functions under Finance Minister, its Sub-Committee (FSDC-SC) operates as an executive arm of the main Council under the chairmanship of Governor, RBI.
• Although India has institutionalised financial stability mechanism, an explicit macroprudential policy framework is yet to develop.

Financial Stability Board

1. It was established in 2009 under G20 by bringing together national authorities, standard setting bodies and international financial institutions.
2. For addressing vulnerabilities and developing and implementing strong policies for financial stability.
3. India is an active member having 3 seats.

ASTROSAT Mission

• ASTROSAT is India’s first dedicated multi-wavelength space observatory.

• AstroSat is the first dedicated Indian astronomy mission aimed at studying celestial sources in X-ray, optical and UV spectral bands simultaneously.
• The payloads cover the energy bands of Ultraviolet (Near and Far), limited optical and X-ray regime (0.3 keV to 100keV).
• One of the unique features of AstroSat mission is that it enables the simultaneous multi-wavelength observations of various astronomical objects with a single satellite.
• AstroSat with a lift-off mass of 1515 kg was launched on September 28, 2015 into a 650 km orbit inclined at an angle of 6 deg to the equator by PSLV-C30 from Satish Dhawan Space Centre, Sriharikota. The minimum useful life of the AstroSat mission is expected to be 5 years.
• The science data gathered by five payloads of AstroSat are telemetered to the ground station at MOX. The data is then processed, archived and distributed by Indian Space Science Data Centre (ISSDC) located at Bylalu, near Bengaluru.

The scientific objectives of AstroSat mission are:

• To understand high energy processes in binary star systems containing neutron stars and black holes;
• Estimate magnetic fields of neutron stars;
• Study star birth regions and high energy processes in star systems lying beyond our galaxy;
• Detect new briefly bright X-ray sources in the sky;
• Perform a limited deep field survey of the Universe in the Ultraviolet region.

ASTROSAT detects a rare galaxy

• India’s first multi-wavelength satellite, which has five unique X-ray and ultraviolet telescopes working in tandem, AstroSat, has detected extreme-UV light from a galaxy, called AUDFs01, 9.3 billion light-years away from Earth,” Inter-University Centre for Astronomy and Astrophysics (IUCAA) said.
• The discovery was made by an international team of astronomers led by Dr Kanak Saha, associate professor of astronomy at the IUCAA, and published on August 24 by ‘Nature Astronomy’, the release said.
• This team comprised scientists from India, France, Switzerland, the USA, Japan and The Netherlands.
• Saha and his team observed the galaxy, which is located in the Hubble Extreme Deep field, through AstroSat.
• Earlier, NASA’s Hubble Space Telescope (HST), a significantly larger than UVIT (UV imaging telescope), did not detect any UV emission (with energygreater than 13.6 eV) from this galaxy because it is too faint, it said.
• AstroSat/UVIT was able to achieve this unique feat because the background noise in the UVITdetector is much less than the ones on HST

Indian astrophysicists spot rare merger of 3 jumbo black holes

• A rare merging of three supermassive black holes has been spotted by a team of astrophysicists from the Indian Institute of Astrophysics (IIA), working with Professor Francoise Combes from the Paris Observatory.

• This is only the third time such an event has been observed and the findings were published as a letter in the journal Astronomy and Astrophysics in June.
• The team were observing the merging of two galaxies — NGC7733 and NGC7734 — in the earth’s celestial neighbourhood when they detected unusual emissions from the centre of the latter and a curious movement of a large bright clump within it, having a different velocity than that of NGC7733. Inferring that this was a separate galaxy, the scientists named it NGC7733N.
• All three merging black holes were part of galaxies in the Toucan constellation. They are quite far away given that the earth’s nearest galactic neighbour — the Andromeda galaxy — is 2.5 million light years away. Yet the paper describes these as nearby galaxies.
• The group observed these galaxies with a near infrared telescope in South Africa.
• Then, later on, because they appeared interesting, we also observed them with the UVIT [onboard the first Indian space observatory ASTROSAT.

What is Final parsec?

• If two galaxies collide, their black holes will also come closer by transferring the kinetic energy to the surrounding gas.
• The distance between the black holes decreases with time until the separation is around one parsec (3.26 light-years).
• The two black holes, however, are then unable to lose any further kinetic energy to get even closer and merge. This is known as the final parsec problem.
• But the presence of a third black hole can solve this problem.
• The two can come closer when another black hole or a star passes by and takes away some of their combined angular momentum.
• Thus, the dual merging black holes merge with each other in the presence of a third.
• Many Active Galactic Nuclei (AGN), or supermassive black hole at the centre of a galaxy, pairs have been detected in the past, but triple AGN are extremely rare, and only a handful have been detected before using X-ray observations.
• Multiple accreting black holes [AGN] may be more common in our universe and especially common in galaxy groups. So the growth of black holes may be driven by such mergers in groups.
• The study used data from the Ultraviolet Imaging Telescope (UVIT) on board the first Indian space observatory ASTROSAT, the European integral field optical telescope called MUSE mounted on the Very Large Telescope (VLT) in Chile and infrared images from the optical telescope (IRSF) in South Africa.