Discoveries On Black Holes By Indian Telescope

Indian scientists have successfully detected and studied an Intermediate-Mass Black Hole (IMBH) located in the faint galaxy NGC 4395, about 4.3 million light-years away.

Key Highlights of Discovery

The discovery was made by Aryabhatta Research Institute of Observational Sciences (ARIES), an autonomous institute of the Department of Science and Technology (DST).
Features of the Black Hole
- The intermediate-mass black hole (IMBH) discovered has a mass of approximately 22,000 times that of the Sun, making it one of the most precisely measured IMBHs.
- Gas clouds were found orbiting the IMBH at a distance of 125 light-minutes (2.25 billion km) with a velocity dispersion of 545 km/s.
- The black hole is accreting matter at just 6% of its theoretical maximum rate, indicating a faint but active galactic nucleus.
Instruments Used: Observations were conducted using the 3.6-metre Devasthal Optical Telescope (DOT) and the 1.3-metre Devasthal Fast Optical Telescope (DFOT), equipped with the Aryabhatta Devasthal Faint Object Spectrograph and Camera (ADFOSC), an indigenously developed system for photometry and spectroscopy.
Technique Applied: The team employed spectrophotometric reverberation mapping to calculate the time delay between emissions, helping determine the black hole’s mass.

What are IMBHs?

Intermediate-Mass Black Holes are black holes that lie between stellar-mass black holes (a few solar masses) and supermassive black holes (millions to billions of solar masses).
IMBHs are expected to have masses ranging from 100 to 100,000 times the mass of the Sun.

Why IMBHs are Difficult to Observe

IMBHs are often found in faint, low-luminosity galaxies, making them hard to detect.
Unlike supermassive black holes, IMBHs typically do not emit bright radiation unless they are actively accreting matter, which further complicates their observation.

Significance of Studying IMBHs

IMBHs are believed to be the seeds of supermassive black holes, playing a crucial role in the evolution of galaxies and black hole formation.
Finding and measuring more IMBHs is vital for filling the missing link in the black hole mass spectrum and for understanding how massive black holes grow over cosmic time.

What is a Black Hole?

Black holes are extremely dense regions in space where gravity is so strong that not even light can escape their pull.
For Example, Cygnus X-1, one of the first discovered stellar black holes, and Sagittarius A*, the supermassive black hole at the center of our Milky Way galaxy.

Types of Black holes Based on Mass

Stellar-Mass Black Holes: Formed from collapsing massive stars, with masses from a few to hundreds of times that of the Sun.
- Many are in binary systems, pulling gas from companion stars, creating X-rays.
Supermassive Black Holes: Found at galaxy centers, these range from hundreds of thousands to billions of solar masses, potentially formed in the early universe.
Intermediate-Mass Black Holes: A theorized “missing link” size range from hundreds to hundreds of thousands of solar masses, hard to detect.
- The recent detection of NGC 4395 Galaxy IMBH is first of its Kind.
Primordial Black Holes: Hypothetically formed soon after the Big Bang; potentially very small or up to 100,000 solar masses

Also Read
UPSC Daily Editorials	UPSC Daily Current Affairs
Daily Current Affairs Quiz	Daily Main Answer Writing
Check Out Previous Years Papers From PW Store	UPSC Test Series
Check Out UPSC NCERT Textbooks From PW Store	Check Out UPSC Modules From PW Store