Sisir Kumar Mitra
Encyclopedia
Sisir Kumar Mitra [or Shishirkumar Mitra] (October 24, 1890 – August 13, 1963) was an India
n physicist
.
He was born and raised in Calcutta
. His parents were the doctor Saratkumari and the school teacher Jaykrishna. At the age of nine he witnessed a hot air balloon
and became intrigued in the phenomenon, so he began studying science. The family moved to Bhagalpur
, where Sisir attended school and the local college. After his father died, his mother supported him through Presidency College
of the University of Calcutta
where he earned a B.Sc. In 1912 he gained his M.S.
at the same institution.
He briefly became a scholar performing research before becoming a teacher. Eventually he taught at Bankura Christian College. In 1914 he married Lilavati Devi.
In 1916, Sisir was invited to join the new postgraduate department of physics at the University Science College. He gained a D.Sc. degree in 1919; then he left for Paris, France to study at the University of Paris
. There he earned a second D.Sc. and would join Marie Curie
at her laboratory. He developed an interest in the new science of radio
communication, and went to the University of Nancy to research this field.
In 1923 he returned to India where he was appointed Khaira Professor of Physics. There, in addition to teaching, he established a laboratory to investigate wireless
. He also initiated a new department at the Calcutta University that later became the Institute of Radio Physics and Electronics.
In 1955 he retired from the university, becoming emeritus professor. He was given charge of the West Bengal Secondary Education Board
, and spent six years organizing this administrative body.
He died following a short illness.
Among his accomplishments were his investigations into the ionosphere
. Dr. Mitra proposed that ultraviolet
light from the sun
created the middle, or E layer, of the ionosphere. He also determined that ions in the ionosphere's F layer were what caused luminescence of the night sky, giving it a dusty hue rather than pitch black. In 1947 he published a reference treatise titled "The Upper Atmosphere" on atmospheric research.
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
n physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
.
He was born and raised in Calcutta
Kolkata
Kolkata , formerly known as Calcutta, is the capital of the Indian state of West Bengal. Located on the east bank of the Hooghly River, it was the commercial capital of East India...
. His parents were the doctor Saratkumari and the school teacher Jaykrishna. At the age of nine he witnessed a hot air balloon
Hot air balloon
The hot air balloon is the oldest successful human-carrying flight technology. It is in a class of aircraft known as balloon aircraft. On November 21, 1783, in Paris, France, the first untethered manned flight was made by Jean-François Pilâtre de Rozier and François Laurent d'Arlandes in a hot air...
and became intrigued in the phenomenon, so he began studying science. The family moved to Bhagalpur
Bhagalpur
Bhagdattpuram was one of the most influential towns in "Aryavarta" . It is supposed to have been concurrent to Patliputra or Patna. Bhagdattpuram finds its mention in the Vedas and Ramayana as well. It is supposed to be the kingdom of Daanvir Karna, the son of Kunti and the Sun God...
, where Sisir attended school and the local college. After his father died, his mother supported him through Presidency College
Presidency College, Kolkata
Presidency University, Kolkata, formerly Hindu College and Presidency College, is a unitary, state aided university, located in Kolkata, West Bengal. and one of the premier institutes of learning of liberal arts and sciences in India. In 2002 it was ranked number one by the weekly news magazine...
of the University of Calcutta
University of Calcutta
The University of Calcutta is a public university located in the city of Kolkata , India, founded on 24 January 1857...
where he earned a B.Sc. In 1912 he gained his M.S.
Master of Science
A Master of Science is a postgraduate academic master's degree awarded by universities in many countries. The degree is typically studied for in the sciences including the social sciences.-Brazil, Argentina and Uruguay:...
at the same institution.
He briefly became a scholar performing research before becoming a teacher. Eventually he taught at Bankura Christian College. In 1914 he married Lilavati Devi.
In 1916, Sisir was invited to join the new postgraduate department of physics at the University Science College. He gained a D.Sc. degree in 1919; then he left for Paris, France to study at the University of Paris
University of Paris
The University of Paris was a university located in Paris, France and one of the earliest to be established in Europe. It was founded in the mid 12th century, and officially recognized as a university probably between 1160 and 1250...
. There he earned a second D.Sc. and would join Marie Curie
Marie Curie
Marie Skłodowska-Curie was a physicist and chemist famous for her pioneering research on radioactivity. She was the first person honored with two Nobel Prizes—in physics and chemistry...
at her laboratory. He developed an interest in the new science of radio
Radio
Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...
communication, and went to the University of Nancy to research this field.
In 1923 he returned to India where he was appointed Khaira Professor of Physics. There, in addition to teaching, he established a laboratory to investigate wireless
Wireless
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications...
. He also initiated a new department at the Calcutta University that later became the Institute of Radio Physics and Electronics.
In 1955 he retired from the university, becoming emeritus professor. He was given charge of the West Bengal Secondary Education Board
West Bengal Board of Secondary Education
The West Bengal Board of Secondary Education is the West Bengal state government administered autonomous examining authority for the Standard 10 examination of West Bengal, India. The examination for the 10th standard is called the Madhyamik Pariksha or secondary examination...
, and spent six years organizing this administrative body.
He died following a short illness.
Among his accomplishments were his investigations into the ionosphere
Ionosphere
The ionosphere is a part of the upper atmosphere, comprising portions of the mesosphere, thermosphere and exosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere...
. Dr. Mitra proposed that ultraviolet
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...
light from the sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
created the middle, or E layer, of the ionosphere. He also determined that ions in the ionosphere's F layer were what caused luminescence of the night sky, giving it a dusty hue rather than pitch black. In 1947 he published a reference treatise titled "The Upper Atmosphere" on atmospheric research.
Awards and honors
- Fellowship of the Royal Society, 1958
- Presidentship of the Indian National Science Academy, 1959-60.
- National Professorship, 1962.
- Padmabhushan, 1962.
- S. K. Mitra Center for Research in Space Environment is named for him.
- The crater MitraMitra (crater)Mitra is a lunar crater that is attached to the western outer rim of the larger crater Mach, on the far side of the Moon. Just to the west of Mitra is Bredikhin, and to the south-southeast lies Henyey. It is named after Sisir Kumar Mitra....
on the MoonMoonThe Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
is named after him.