EDITORIAL BORD
37
Transcript of EDITORIAL BORD
EDITORIAL BORD EDITORIAL BORD 0303
0404
DIPAK DEY DIPAK DEY 0505
1010
1212
. DR AMALENDU. DR AMALENDU BANDYOPADHYAYBANDYOPADHYAY
GOURAV BANERJEE GOURAV BANERJEE 1414
PHOTOGRAPHY SECTION PHOTOGRAPHY SECTION 1919
--
2222
0 0 , , . DR SANKAR KUMAR NATH. DR SANKAR KUMAR NATH 2525
2727
9 9 9 9 - - > >> > 2828
3030
THE SOLAR SYSTEM THE SOLAR SYSTEM ALEXANDRA ALBANI ALEXANDRA ALBANI 3131
OUR ACTIVITY OUR ACTIVITY 3737
CONTENTSCONTENTS
[email protected]
@BhabanaBijnan
02
Co-editor :Co-editor : Puja Adhikary
President :President : Dipak Dey
SOME IMPORTANT MEMBER OF OUR ORGANIZATION “BIJÑNA BHBANBIJÑNA BHBAN” : PRESIDENT : PRESIDENT : DIPAK DEYDIPAK DEY
VICE PRESIDENT : VICE PRESIDENT : PANKAJ SARKAR PANKAJ SARKAR
GENERAL SECRETARY : GENERAL SECRETARY : SANTU CHAKRABORTYSANTU CHAKRABORTY
TREASURER : TREASURER : SUMITA ROY SUMITA ROY
IT & SOCIAL NETWORK HEAD : IT & SOCIAL NETWORK HEAD : SUMAN SARKAR
COORDINATOR : COORDINATOR : ROHIT SHAWROHIT SHAW CO-COORDINATOR : CO-COORDINATOR : BIDHAN HALDERBIDHAN HALDER MAGAZINE MAGAZINE HEAD :HEAD : ABHIRUP DAS
OTHERS IMPORTANT MEMBER : Sagarika Banerjee, Tarun Banerjee, Subham Das, Susanto Ranjit,John Dutta etc.
EDITORIAL BORDEDITORIAL BORD ofof
03
> > > > > >>> >> > > > >, ', '' ' 0 0 > Q > Q ,, T T > 9 > 9 > > , , , , 0 Z0 Z > > \] > > \] ? ? ^ ^ _ _ '' '' > > 0 0 , , > > , , _ > > _ > > , , > > > > > > , , \] ^ ]\] ^ ], , 0 0 ^ ^ , , > > '' --'' , , -- > >\ > >\ , , 0 0 > > 0 0 > > , ', ' ' ' , , aa, , , , ,, > > , , > >> Z > >> Z ] ]
04
! 0 ? > > , >> >> > 9? 0 Q^, Q> 0 ^ 0 > 0 d > Q^ Q> > , > 0 , 0 f > 9 Z, >, > > > j > 0 >> T Q> m> , n o 0 Q q > j Q> >,
> 0 > ? 0 > ? ? > > > a
( West Bengal, India )
05
> ? > > >, > > > T 0 ? > > { > 0 ? > > 0 "" > , (SPACE POLUTION )
SPACE POLUTION SPACE POLUTION ?? Q n o 0 9 , \ > 9 , 0 9 >, 0 ^ > >, > 9 > > \\
9 GOCE Satellite 2013 ( ), Upper Atmosphere Research Satellite (UARS) } 2011 ( . ), Skylab space station > 2009 ( ), Pegasus 2 Satellite 1979 (. ),
Tiangong 1 Space Lab > 2018 > 0
This is one of the first images taken by the DC-8 aircraft which observed the re-entry of Jules Verne ATV over the
Pacific Ocean. (Image credit: ESA)
06
Space war _ _ > > _ , 0 > 0 > > > n Q>, > d, , Anti- satellite weapons (ASAT) > 0 Q> - q-> > > > > ! 0 > 0 > > n o , >
: : > > > > > > , , > Q > > Q > , , ] > > ] > > ] ] ] ] ““The Most Deadliest Pollution” The Most Deadliest Pollution” > 0 > 0 , , > > (Mental Pollution)(Mental Pollution) Visual Visual -- 0 0 , , -- 0 0 , , > > > >-- > > ? ? > >- - > > > >
A-SAT () Develop by DRDO
07
] 0 > 0 >
0
0 ]- ]- - 0 > > > > ? > % > > ]- > > ]- >>
-
-
-
-
- & - )
- - . /
-
08
0 >> ]- > > ]- >, > "\" > . . 0 >> ] > ] > \ . > > > >, ? ! Q > ^ ^, 9 > > > > 0
> > } > 0 >> m> , 0 > > > 0 > .............To be continued
09
... , ! ! & & & &, - - -- & & & - & , - ! /& -- ! & &3 && -- ' 6 , ! ! 9!:
... , 3 & & ! !
( West Bengal, India )
10
6 , 3 =3 / ! > & @ &, & B & /& 6 ! , ! ! 6
11
& & , ! & !&!
E & & & 3!
& 6 !, !J >&
/ & 6 J
&!& & &, & & 6,
& & 6
!: & , & &
39 ! ! !
( West Bengal, India )
12
!& &
& & & / &
& !
!J &
13
Let us come to know about a great man of India – Dr. Amalendu Bandyopadhyay, the Founder Director of the Positional Astronomy Centre, Kolkata and the person who literally started astronomy popularization in India. Dr. Amalendu Bandyopadhyay passed away at around 20:30 pm on June 22, 2020 at his home at Kolkata at an age of 90. Being a researcher in astrophysics myself, a future astronomer and a close acquaintance of Dr.
Dr. Amalendu BandyopadhyayDr. Amalendu Bandyopadhyay [The story of a Star Warrior]
By : Gourav BanerjeeBy : Gourav Banerjee [Research scholar (astrophysics),[Research scholar (astrophysics),
CHRIST, Bangalore.]CHRIST, Bangalore.]
14
Amalendu Bandyopadhyay, I feel it is my moral duty to introduce this great person to anyone who loves astronomy.
Born on February 1, 1930 in the Mugkalyan village of Howrah district, West Bengal, Dr. Amalendu Bandyopadhyay completed his school education from his village. Then he moved to Varanasi and completed MSc. in Applied Mathematics from the esteemed Banaras Hindu University (BHU). It was here where he received the company of the eminent mathematician, Dr. V.V. Narlikar – father of the world renowned Indian cosmologist Dr. Jayanta Vishnu Narlikar (Founder of the Inter University Centre for Astronomy and Astrophysics, Pune). Dr. V.V. Narlikar was the mathematics teacher of Dr. Bandyopadhyay, and it was he who inspired Dr. Bandyopadhyay to pursue astronomy in future. After MSc., Amalendu Bandyopadhyay started his career as a lecturer of a college at Varanasi with a monthly salary of 192/-.
Then in 1956, with untiring efforts of another legendary Indian physicist Dr. Meghnad Saha, an unit for research in positional astronomy – the Nautical Almanac Unit - was established at Kolkata. The primary objective of this unit was to precisely compute the position of planets, stars and other heavenly objects and dates of different celestial phenomenon for each day of every year. This branch of astronomy, known as ‘Positional Astronomy’ is extremely important. Every astronomical observatory, each observational astronomer, calendar maker, festival setter needs these data to accurately perform astronomical observations and even different festivals all over India. But Positional Astronomy was in its infancy in India during those days. As a result, India had to purchase these data from USA, France spending huge costs. These calculations were meticulously done by those countries and the results were published in the form of a book, termed as ‘Astronomical Ephimeries’.
Dr. Bandyopadhyay joined the Nautical Almanac Unit, Kolkata in 1956 and remained here as an Assistant Scientist till 1962. For the next six years he was involved in atmospheric sciences research necessary for flying of airplanes. Later in 1968, he took over as the Director of the Nautical Almanac Unit. And then began his historic two-way fights – the relentless efforts which turned him into a legend.
15
It was during 1960s only when Amalendu Bandyopadhyay realized that India needs to prepare its own Astronomical Ephimeries. Why will we spend dollars to buy data from other countries? During those days, the Nautical Almanac Unit was a small unit under the Department of Meteorology, Govt. of India. Hence, in 1968, after taking over the complete responsibility of the Unit, he started a tireless campaign to establish a separate department for positional astronomy directly under the Government of India. He was also clear about another objective – this new department has to be established in Kolkata. This was because during that period Kolkata was the centre for education in India. Skilled workers, researchers, infrastructure – everything were readily available. His request for establishing such a separate department, that too in Kolkata, was opposed by the Indian Government. Mrs. Indira Gandhi – the iron lady of India- clearly mentioned that if such a department will be established, that will be in Bangalore.
An unstoppable fight for 12 years continued. Dr. Bandyopadhyay had only two weapons – his in-depth knowledge in positional astronomy and indomitable personality. Ultimately on April 26, 1980, his dream turned into immense success. Positional Astronomy Centre (PAC), a separate centre for positional astronomy calculations under the Government of India was established in Kolkata. He was elected as the Founder Director of PAC. Then, within another year, under the able leadership of Amalendu Bandyopadhyay, India published its own Ephimeries – now known as the Indian Astronomical Ephimeries. India is presently one among eight nations in the world which can produce their own Astronomical Ephimeries. More than 200 observatories from over 40 countries currently buy the data from India. It was a paradigm shift – once we had to buy such data from abroad, now India earns foreign exchange by selling these data. The credit for such a historical achievement goes to this simple, humble Bengali astronomer - Dr. Amalendu Bandyopadhyay.
He retired from PAC on February 1, 1988 and then joined the M.P. Birla Planetarium, Kolkata in 1993 as a Senior Scientist. Dr. Bandyopadhyay took an instrumental role in providing a solid structure to the academic stature of the Institute. Till his last day, he remained as an active member of the Institute. In the meantime, since 1970, Dr. Bandyopadhyay started another relentless effort – popularization of astronomy among common
16
public and students in the remotest parts of Bengal and East India. Within few years, he became a pioneer of science communication movement in West Bengal and India.
Dr. Amalendu was a crusader of sorts. Since 1970s, he travelled to remotest corners of Bengal and delivered popular talks on astronomy with two visions – popularizing the subject among the masses and enlighten them with true knowledge so that the burden of superstitions can go down. His talks were mesmerizing, blended with stories and truth in such a way that through such talks he used to break apart the very foundation of astrology – a false subject practiced by numerous astrologers till now in India. After his retirement from the PAC, he spent his life’s savings to purchase a four-inch telescope, three German slide projectors, two screen projectors and a voltage stabilizer to make his talks more interesting.
But the battle to promote astronomy and debunking astrology – a menace of the society was not easy. This is because there are numerous business houses and unscrupulous persons who feed on peoples’ belief on superstitions. Dr. Bandyopadhyay received numerous life threatenings from various astrologers (who show them as the healers of all pain of common man!!!) and business houses in his lifetime. He never compromised and stood high always with his inborn fighting spirit against astrology.
Awards and Honours: 1995: Recipient of National Award from the Govt. of India for best popularization of astronomy in India. He was the first Indian to receive a National award for popularization of astronomy.
2001: Recipient of the prestigious Gopal Chandra Bhattacharya Memorial Award under the Govt. of West Bengal for best popularization of astronomy in West Bengal.
2003: Recipient of honorary DSc. From the University of Burdwan, West Bengal for best popularization of astronomy in India. He is the only Indian to receive an honorary DSc. for popularization of astronomy.
17
2012: Recipient of the prestigious Jagattarini Gold Medal from the University of Calcutta for best popularization of astronomy in Bengali language.
2013: Recipient of the prestigious G.P.Chatterjee Memorial Award from the Indian Science Congress Association for best contribution in positional astronomy study in India.
Apart from these, Dr. Amalendu Bandyopadhyay was elected as the Life Member of the International Astronomical Union, Astronomical Society of India, British Astronomical Association and an elected Fellow of the prestigious Royal Astronomical Society and Academy of Science and Technology, West Bengal.
He has passed away, but his contributions will remain eternal in the minds of countless people whom he inspired. I was also one among those innumerable people. Now, it is our duty to carry forward his visions – to turn India into a nation full of astro - ‘nomy’, not ‘logy’.
18
PHOTOGRAPHY SECTIONPHOTOGRAPHY SECTION
THE WEARY TRAVELER IS LYING ON THE ROAD AS HE WALKS, AND THE TREES ON THE ROAD ARE PEEKING AT HIM.
PHOTOGRAPHY BY : AKASH DEY
19
A GLIMPSE OF THE CITY OF JOY PHOTOGRAPHY BY : SUMIT BASAK
FIND THE PEACE PHOTOGRAPHY BY : SUMIT BASAK
20
SIR JOHN ANDERSON ROCK GARDEN, DARJEELING PHOTOGRAPHY BY : PUJA ADHIKARY
21
>> >> Q> > Q> > > > > \] > \] ? ? > > > >
\] Q> \] Q> Q> Q> ''-- ' ' Q> Q> , , ''--' ' ''>>' ' , , > >
n n \ \ 0 Q> 0 Q> \] > \] > > > > >
[ ]
--
( West Bengal, India )
22
> > \> > \ -- ] ]
]> > ]> > , , \] >\] > > > , , q q > > ] > ] > , , , , > > q >> > q > > > > > -87STS-87STS > >, , > > > > > Q > Q > > Q Q> Q> > > Q Q> Q> > >
, , > > ] > > ] > > 0 o ] 0 o ] > >
> >,, > >, , > > \ \ > > > 0 > Z> 0 > Z 0 0 , , > >
23
0 0 \ Q \ Q
0 Q> > 0 Q> > ''' ' ''' ' Q> > Q> > \ Q> > ‘’ \ Q> > ‘’ > 0 \>> 0 \> \ Q \ Q , , Q>Q> Q>Q> > > >q > > >q--_ _ > >, , \] \] > > ] > > > ] > > >
24
> 0 > 0 , , , , ^ 0 ^ 0 -- > > - - > > > > > > > > > T > > T > , , ,, \ \ \ \ , , > > - - > \ > \ > > ] > > ] Q> > Q> > , , > > 0 0 >> >> Carcinogen Carcinogen , , > 0 > 0 > 9 > 9 : : \ \ ,, o o, , >>, , , , 9 9 – – , , , , , , \ \ :: \ \ > > > > > > Q QQ Q : : Q Q Q Q , , 0 Q Q 0 Q Q 9 9 \ \ :: ª \ ª \ -- > >
, , Dr. Sankar Kumar NathDr. Sankar Kumar Nath
SENIOR ONCOLOGIST OF CULCUTTA MEDICAL COLLEGE, SENIOR ONCOLOGIST OF CULCUTTA MEDICAL COLLEGE, R.G. KAR MEDICAL COLLEGE AND BANKURA SAMMILANI R.G. KAR MEDICAL COLLEGE AND BANKURA SAMMILANI MEDICAL COLLEGE.MEDICAL COLLEGE.
MBBS, DMRT
25
:: Fungus Fungus -- > > T T :: :: , , CarcinogenCarcinogen > > > >, , > > , , > o> o > > > > , , ,, , , >>, , > >
, , 0 0 :: > Q> > Q>, , , , ,, > >,, Q> Q>, , , , , , , , , , >>,, >>, , > > -- :: , , , , > >> > >> ,, >> >> , , , , , , , , 0 0 33 -- :: >>, , , , , , , , , , ,, > >> >, , , , , , > >, , , , , , > > , ,
0 0 :: > > 3 3 Q Q \ \ > > > \ > > > \ > > \ > > \ > > -- \ \ 00, , Q>Q>, , Q> 9 Q> 9
:: > > > > > > > 0 > > 0 > > >
26
& ! ! &3 & ! ! &3, , & ! ! & / &3 & ! ! & / &3
& && &, , & & O3 >&& & O3 >&, , @ ! &3 @ ! &3 ,,
! > ! > ?? & ! & & ! && ! & & ! &, , > &> > &> '' & &''
''& & &&& & &&,, & & & &''
6> ! ! ! 6> ! ! !, , 6 && ! !6 && ! !
! ! 6! ! ! : ! ! 6! ! ! : O3> > @ ! /O3> > @ ! / > & > & , ,
& & ! ! > & & ! ! > > > ,,
O3> ! O3> !
( West Bengal, India )
27
, , , , Q > 9 Q > 9 99- - 9 9 ''--'- '- q q ''99' ' -- > 0 > > 0 > --
;; --> > > > ;; f f ’ 9’ 9
9 9 9 9 ''' (' ( > > , , ) ) ] ] ! ! _ 0 _ 0 9 9 9 9 ] ] > > >> >> , C, C = 4 = 4 -t-t 160. 160. Q Q >> = t = t ] ] C C ^ 99 ^ 99 ''' ' > 9 9 > 9 9 ? ? Q Q ] ] 40 40 Q Q 4.4 4.4 > 9 9 > 9 9
-- > >> >
( West Bengal, India ) TELESCOPES & OPTICS SPECIALISTTELESCOPES & OPTICS SPECIALIST
28
45 45 Q Q 7.2 7.2 > > 20 20 9 9 9 9 = 4 45 - 160 = 180 - 160 = 20. C x = 4 45 - 160 = 180 - 160 = 20. C x ] ] 70 70 Q Q 21.11 21.11 > 9 9> 9 9-- o > o > > 99 > 99 160 160 200, 200, ] ] ? ? > > 80 80 9090 Q Q > > > > 26.66 26.66 32.22 32.22 '' ' '
29
,, ,,
, ,
,, " # " #
( # # ( # #
- -,, - #- - #-
-/ # - # -/ # - # - -
- 4 " - - - 4 " - - - - " - - "
# #
( West Bengal, India )
30
The solar system is made up of Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The study of the data relating to each planet has allowed us to divide them into two groups: the terrestrial planets, or similar to Earth, (Mercury, Venus, Earth and Mars) and the jovian planets similar to Jupiter, (Jupiter, Saturn, Uranus and Neptune). The biggest difference that distinguishes these two groups is the size: the Jupiter planets are in fact larger and are also called giant planets. Due to the presence of the asteroid belt between Mars and Jupiter, the planets between the belt and the Sun are called inner planets, while those beyond the belt are called outer planets. Other differences between the planets are the composition, density and speed of rotation. While the density of terrestrial planets is about 5 times that of water, that of the Jupiter planets is around one and a half times. The materials that make up the various planets are of three types: gases, such as hydrogen and helium,
The solar systemThe solar system ( Bergamo, Italy )
By : Alexandra AlbaniBy : Alexandra Albani
31
rock-like materials such as silicate minerals and metallic iron, and ices which include ammonia, methane, carbon dioxide and water. The escape velocity is the velocity that a body must acquire in order to leave the atmosphere and therefore move away from the planet. The origin of the Solar System. Regarding the origin of the Solar System with the passage of time, a hypothesis called the nebular hypothesis has been formulated, according to which all the planets originated from a huge cloud of dust and gas, called the primordial nebula, formed by all those materials that we can find today on the planet of the system. Around 5 billion years ago this cloud of gas and heavy grains began to contract due to gravitational interactions and as this contraction took place, it kept increasing the speed of rotation according to the angular momentum principle. A moment came when the centrifugal force balanced the gravitational thrust towards the interior and the cloud turned into a flattened disk with a concentration of materials in the center that made up the protosole. Following the formation of this protosole, the phase of gravitational heating began, during which the temperature in the area of the inner planets began to decrease, favoring the aggregation of materials and the condensation of others, to give rise to planetesimals. Following the various collisions, the proto planets originated, which increased more and more to form what today are the 4 inner planets. Those aggregates of matter that did not form the planets remained in orbit between Mars and Jupiter and form what is now called the asteroid belt. Simultaneously with the formation of the inner planets there was that of the outer planets, which having lower temperature due to the greater distance from the sun, became an agglomeration of ices. Several satellites also formed around these outer planets.
The "dome" that surrounds us is called the celestial vault and has an apparent motion.Until 1600 it was thought
32
that there were 600 stars.From 1609, thanks to Galileo Galilei, the telescope began to be used.
LIGHT: it is an electromagnetic radiation that propagates with a wave motion. Electromagnetic waves have a crest and a belly, and are characterized by a wavelength (the distance between two crests or between two bellies) and a frequency.The shorter the wavelength, the higher the frequency.The information that comes from space travels in the form of electromagnetic waves and propagates both through the vacuum and through means transparent to them. To reach us, the light takes a time proportional to the distance at which the light source is located. The sunlight takes 8 minutes to arrive on our planet. In astronomy, to express the distances of celestial bodies, the light-year is used (the distance traveled in a year by light in a vacuum (9460 km). Stars and galaxies. Stars are celestial bodies within which a huge amount of energy that propagates in the universe.In the nucleus of the stars hydrogen is transformed into helium (4 hydrogen nuclei form 1 helium nucleus). The stars are very far away and hold their positions fixed. At the poles, all stars are circumpolar, meaning they make a complete rotation around the polar star. If a star rises and sets it is called occidua. The stars group together to form galaxies. Earth is part of the Milky Way (or Galaxy). It has a disc shape in which spiral arms can be seen, in one of which the Sun is located. Andromeda and the Magellanic Clouds are visible to the naked eye. Constellations are groupings of stars. There are 88 and they allow us to divide the universe into sectors. 12 are of the zodiac, and are on the plane of the earth's orbit.
33
The stars in a constellation are at enormous distances from each other. The brightest star in a constellation is called Alpha.The mass: from 0.02 to 200 times the mass of the sun. The dimensions: they vary from 0.1 to 1000 times the radius of the sun. The density: it can also be different The measurement of the surface temperature (on which the color of the star depends). The hottest stars are blue-blue-white, the coldest (3000-8000 ° C) red- orange-yellow. Brightness is measured by apparent magnitude. It depends on the amount of light emitted and the distance from the Earth. Sirius, for example, is brighter than the Sun, but further away. The solar system is a planetary system consisting of a variety of celestial bodies kept in orbit by the gravitational force of the Sun, which also includes the Earth: with a diameter of about 120-130 AU (if understood as the area of space that is subjected to the solar wind, leaving out the immense area subjected to solar gravity alone) is located in the Orion arm of the Milky Way, orbiting around the galactic center at a distance of 30000 al and a speed of 230 km / s; it is estimated that the solar system takes about 230 million years to complete one revolution around the galactic center.
Consisting of the Sun, which alone possesses 99.86% of the power of the entire system, and eight planets (four inner rocky planets and four outer gas giants) and five dwarf planets, their respective natural satellites, and many other bodies minor, the latter category includes asteroids, largely divided between two asteroid belts (the main belt and the Kuiper belt), comets (mainly located in the hypothetical Oort cloud), meteoroids and interplanetary dust.
34
In order of distance from the Sun, the eight planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune; the five dwarf planets are: Ceres, located in the main asteroid belt, Pluto, Haumea, Makemake, and Eris. The solar wind, a flow of plasma generated by the continuous expansion of the solar corona, permeates the entire solar system, creating a bubble in the interstellar medium known as the heliosphere, which extends beyond half of the diffuse disk. celestials of the solar system were already known since ancient times, the concept itself was ignored as there was mostly an idea of a geocentric system with the Earth at the center of the universe. One of the first to imagine a heliocentric system was Aristarchus of Samo, but his ideas did not take hold in the community of philosophers and thinkers of the time.
It was only in the sixteenth century that Nicolaus Copernicus proposed the modern vision of the solar system, with the Sun at the center and the planets known at the time to orbit around. The only known bodies in the solar system, however, were only the four terrestrial planets, Jupiter, Saturn, the Sun and the Moon. In the following century, with the invention of Galileo Galilei's telescope, other minor bodies were discovered, such as the Medici satellites, the rings of Saturn and some comets and for about 200 years it was not thought that there could be other objects in the solar system, in particular was the firm belief that the planets were only those then known. In 1781, the discovery of Uranus by William Hersche questioned the preconceptions that the scientific community had, generating doubts regarding the possibility that transuranic planets existed.
A few years later, in 1801, Giuseppe Piazzi declared that he had discovered a new planet, between the orbits of Mars and Jupiter; it was actually Ceres. The conclusion came by excluding that it could be a comet and not
35
knowing other objects other than planets and comets, completely unaware that he had discovered a new type of object, the asteroid. Since then the discoveries of new objects multiplied, in particular many new asteroids were discovered. In 1846 a planet was discovered in a completely revolutionary way: before direct observation, the perturbations of the orbit of Uranus were calculated and it was deduced that a planet had to exist at a precise point in space to justify the discrepancies observed. A few days later, Johann Gottfried Galle and Heinrich Louis d'Arrest confirmed the presence of Neptune less than one degree away from the calculated point.
In 1930, the discovery of Pluto increased the number of known planets to nine, which was then believed to be an object of much greater mass than it actually is. In the 1950s Jan Oort hypothesized the existence of a nursery of comets far beyond the orbits of known planets, located tens of thousands of AU from the Sun, the Oort cloud, which when disturbed significantly changed their orbit up to to arrive in the internal area of the system. In 1992, the discovery of Albion restarted the search for trans- Neptunian objects. The advent of automatic search systems allowed the discovery of thousands of objects with a diameter between 50 and 2500 km. The discovery of Eris, similar in size to Pluto, in 2005 challenged the very definition of planet, which was changed and formalized in 2006 by the International Astronomical Union, downgrading Pluto to a dwarf planet and bringing the total number of planets back to eight. The most accredited theories on the formation of the solar system describe its birth 4.6 billion years ago starting from the fragmentation and gravitational collapse of a gigantic molecular cloud with a diameter of 65 light years.One of these fragments, with an initial size of 2000-20000 astronomical units, collapsed into what is known as the protoplanetary disk. The main components of this primordial forge were 98% primo.
36
37
0404
DIPAK DEY DIPAK DEY 0505
1010
1212
. DR AMALENDU. DR AMALENDU BANDYOPADHYAYBANDYOPADHYAY
GOURAV BANERJEE GOURAV BANERJEE 1414
PHOTOGRAPHY SECTION PHOTOGRAPHY SECTION 1919
--
2222
0 0 , , . DR SANKAR KUMAR NATH. DR SANKAR KUMAR NATH 2525
2727
9 9 9 9 - - > >> > 2828
3030
THE SOLAR SYSTEM THE SOLAR SYSTEM ALEXANDRA ALBANI ALEXANDRA ALBANI 3131
OUR ACTIVITY OUR ACTIVITY 3737
CONTENTSCONTENTS
[email protected]
@BhabanaBijnan
02
Co-editor :Co-editor : Puja Adhikary
President :President : Dipak Dey
SOME IMPORTANT MEMBER OF OUR ORGANIZATION “BIJÑNA BHBANBIJÑNA BHBAN” : PRESIDENT : PRESIDENT : DIPAK DEYDIPAK DEY
VICE PRESIDENT : VICE PRESIDENT : PANKAJ SARKAR PANKAJ SARKAR
GENERAL SECRETARY : GENERAL SECRETARY : SANTU CHAKRABORTYSANTU CHAKRABORTY
TREASURER : TREASURER : SUMITA ROY SUMITA ROY
IT & SOCIAL NETWORK HEAD : IT & SOCIAL NETWORK HEAD : SUMAN SARKAR
COORDINATOR : COORDINATOR : ROHIT SHAWROHIT SHAW CO-COORDINATOR : CO-COORDINATOR : BIDHAN HALDERBIDHAN HALDER MAGAZINE MAGAZINE HEAD :HEAD : ABHIRUP DAS
OTHERS IMPORTANT MEMBER : Sagarika Banerjee, Tarun Banerjee, Subham Das, Susanto Ranjit,John Dutta etc.
EDITORIAL BORDEDITORIAL BORD ofof
03
> > > > > >>> >> > > > >, ', '' ' 0 0 > Q > Q ,, T T > 9 > 9 > > , , , , 0 Z0 Z > > \] > > \] ? ? ^ ^ _ _ '' '' > > 0 0 , , > > , , _ > > _ > > , , > > > > > > , , \] ^ ]\] ^ ], , 0 0 ^ ^ , , > > '' --'' , , -- > >\ > >\ , , 0 0 > > 0 0 > > , ', ' ' ' , , aa, , , , ,, > > , , > >> Z > >> Z ] ]
04
! 0 ? > > , >> >> > 9? 0 Q^, Q> 0 ^ 0 > 0 d > Q^ Q> > , > 0 , 0 f > 9 Z, >, > > > j > 0 >> T Q> m> , n o 0 Q q > j Q> >,
> 0 > ? 0 > ? ? > > > a
( West Bengal, India )
05
> ? > > >, > > > T 0 ? > > { > 0 ? > > 0 "" > , (SPACE POLUTION )
SPACE POLUTION SPACE POLUTION ?? Q n o 0 9 , \ > 9 , 0 9 >, 0 ^ > >, > 9 > > \\
9 GOCE Satellite 2013 ( ), Upper Atmosphere Research Satellite (UARS) } 2011 ( . ), Skylab space station > 2009 ( ), Pegasus 2 Satellite 1979 (. ),
Tiangong 1 Space Lab > 2018 > 0
This is one of the first images taken by the DC-8 aircraft which observed the re-entry of Jules Verne ATV over the
Pacific Ocean. (Image credit: ESA)
06
Space war _ _ > > _ , 0 > 0 > > > n Q>, > d, , Anti- satellite weapons (ASAT) > 0 Q> - q-> > > > > ! 0 > 0 > > n o , >
: : > > > > > > , , > Q > > Q > , , ] > > ] > > ] ] ] ] ““The Most Deadliest Pollution” The Most Deadliest Pollution” > 0 > 0 , , > > (Mental Pollution)(Mental Pollution) Visual Visual -- 0 0 , , -- 0 0 , , > > > >-- > > ? ? > >- - > > > >
A-SAT () Develop by DRDO
07
] 0 > 0 >
0
0 ]- ]- - 0 > > > > ? > % > > ]- > > ]- >>
-
-
-
-
- & - )
- - . /
-
08
0 >> ]- > > ]- >, > "\" > . . 0 >> ] > ] > \ . > > > >, ? ! Q > ^ ^, 9 > > > > 0
> > } > 0 >> m> , 0 > > > 0 > .............To be continued
09
... , ! ! & & & &, - - -- & & & - & , - ! /& -- ! & &3 && -- ' 6 , ! ! 9!:
... , 3 & & ! !
( West Bengal, India )
10
6 , 3 =3 / ! > & @ &, & B & /& 6 ! , ! ! 6
11
& & , ! & !&!
E & & & 3!
& 6 !, !J >&
/ & 6 J
&!& & &, & & 6,
& & 6
!: & , & &
39 ! ! !
( West Bengal, India )
12
!& &
& & & / &
& !
!J &
13
Let us come to know about a great man of India – Dr. Amalendu Bandyopadhyay, the Founder Director of the Positional Astronomy Centre, Kolkata and the person who literally started astronomy popularization in India. Dr. Amalendu Bandyopadhyay passed away at around 20:30 pm on June 22, 2020 at his home at Kolkata at an age of 90. Being a researcher in astrophysics myself, a future astronomer and a close acquaintance of Dr.
Dr. Amalendu BandyopadhyayDr. Amalendu Bandyopadhyay [The story of a Star Warrior]
By : Gourav BanerjeeBy : Gourav Banerjee [Research scholar (astrophysics),[Research scholar (astrophysics),
CHRIST, Bangalore.]CHRIST, Bangalore.]
14
Amalendu Bandyopadhyay, I feel it is my moral duty to introduce this great person to anyone who loves astronomy.
Born on February 1, 1930 in the Mugkalyan village of Howrah district, West Bengal, Dr. Amalendu Bandyopadhyay completed his school education from his village. Then he moved to Varanasi and completed MSc. in Applied Mathematics from the esteemed Banaras Hindu University (BHU). It was here where he received the company of the eminent mathematician, Dr. V.V. Narlikar – father of the world renowned Indian cosmologist Dr. Jayanta Vishnu Narlikar (Founder of the Inter University Centre for Astronomy and Astrophysics, Pune). Dr. V.V. Narlikar was the mathematics teacher of Dr. Bandyopadhyay, and it was he who inspired Dr. Bandyopadhyay to pursue astronomy in future. After MSc., Amalendu Bandyopadhyay started his career as a lecturer of a college at Varanasi with a monthly salary of 192/-.
Then in 1956, with untiring efforts of another legendary Indian physicist Dr. Meghnad Saha, an unit for research in positional astronomy – the Nautical Almanac Unit - was established at Kolkata. The primary objective of this unit was to precisely compute the position of planets, stars and other heavenly objects and dates of different celestial phenomenon for each day of every year. This branch of astronomy, known as ‘Positional Astronomy’ is extremely important. Every astronomical observatory, each observational astronomer, calendar maker, festival setter needs these data to accurately perform astronomical observations and even different festivals all over India. But Positional Astronomy was in its infancy in India during those days. As a result, India had to purchase these data from USA, France spending huge costs. These calculations were meticulously done by those countries and the results were published in the form of a book, termed as ‘Astronomical Ephimeries’.
Dr. Bandyopadhyay joined the Nautical Almanac Unit, Kolkata in 1956 and remained here as an Assistant Scientist till 1962. For the next six years he was involved in atmospheric sciences research necessary for flying of airplanes. Later in 1968, he took over as the Director of the Nautical Almanac Unit. And then began his historic two-way fights – the relentless efforts which turned him into a legend.
15
It was during 1960s only when Amalendu Bandyopadhyay realized that India needs to prepare its own Astronomical Ephimeries. Why will we spend dollars to buy data from other countries? During those days, the Nautical Almanac Unit was a small unit under the Department of Meteorology, Govt. of India. Hence, in 1968, after taking over the complete responsibility of the Unit, he started a tireless campaign to establish a separate department for positional astronomy directly under the Government of India. He was also clear about another objective – this new department has to be established in Kolkata. This was because during that period Kolkata was the centre for education in India. Skilled workers, researchers, infrastructure – everything were readily available. His request for establishing such a separate department, that too in Kolkata, was opposed by the Indian Government. Mrs. Indira Gandhi – the iron lady of India- clearly mentioned that if such a department will be established, that will be in Bangalore.
An unstoppable fight for 12 years continued. Dr. Bandyopadhyay had only two weapons – his in-depth knowledge in positional astronomy and indomitable personality. Ultimately on April 26, 1980, his dream turned into immense success. Positional Astronomy Centre (PAC), a separate centre for positional astronomy calculations under the Government of India was established in Kolkata. He was elected as the Founder Director of PAC. Then, within another year, under the able leadership of Amalendu Bandyopadhyay, India published its own Ephimeries – now known as the Indian Astronomical Ephimeries. India is presently one among eight nations in the world which can produce their own Astronomical Ephimeries. More than 200 observatories from over 40 countries currently buy the data from India. It was a paradigm shift – once we had to buy such data from abroad, now India earns foreign exchange by selling these data. The credit for such a historical achievement goes to this simple, humble Bengali astronomer - Dr. Amalendu Bandyopadhyay.
He retired from PAC on February 1, 1988 and then joined the M.P. Birla Planetarium, Kolkata in 1993 as a Senior Scientist. Dr. Bandyopadhyay took an instrumental role in providing a solid structure to the academic stature of the Institute. Till his last day, he remained as an active member of the Institute. In the meantime, since 1970, Dr. Bandyopadhyay started another relentless effort – popularization of astronomy among common
16
public and students in the remotest parts of Bengal and East India. Within few years, he became a pioneer of science communication movement in West Bengal and India.
Dr. Amalendu was a crusader of sorts. Since 1970s, he travelled to remotest corners of Bengal and delivered popular talks on astronomy with two visions – popularizing the subject among the masses and enlighten them with true knowledge so that the burden of superstitions can go down. His talks were mesmerizing, blended with stories and truth in such a way that through such talks he used to break apart the very foundation of astrology – a false subject practiced by numerous astrologers till now in India. After his retirement from the PAC, he spent his life’s savings to purchase a four-inch telescope, three German slide projectors, two screen projectors and a voltage stabilizer to make his talks more interesting.
But the battle to promote astronomy and debunking astrology – a menace of the society was not easy. This is because there are numerous business houses and unscrupulous persons who feed on peoples’ belief on superstitions. Dr. Bandyopadhyay received numerous life threatenings from various astrologers (who show them as the healers of all pain of common man!!!) and business houses in his lifetime. He never compromised and stood high always with his inborn fighting spirit against astrology.
Awards and Honours: 1995: Recipient of National Award from the Govt. of India for best popularization of astronomy in India. He was the first Indian to receive a National award for popularization of astronomy.
2001: Recipient of the prestigious Gopal Chandra Bhattacharya Memorial Award under the Govt. of West Bengal for best popularization of astronomy in West Bengal.
2003: Recipient of honorary DSc. From the University of Burdwan, West Bengal for best popularization of astronomy in India. He is the only Indian to receive an honorary DSc. for popularization of astronomy.
17
2012: Recipient of the prestigious Jagattarini Gold Medal from the University of Calcutta for best popularization of astronomy in Bengali language.
2013: Recipient of the prestigious G.P.Chatterjee Memorial Award from the Indian Science Congress Association for best contribution in positional astronomy study in India.
Apart from these, Dr. Amalendu Bandyopadhyay was elected as the Life Member of the International Astronomical Union, Astronomical Society of India, British Astronomical Association and an elected Fellow of the prestigious Royal Astronomical Society and Academy of Science and Technology, West Bengal.
He has passed away, but his contributions will remain eternal in the minds of countless people whom he inspired. I was also one among those innumerable people. Now, it is our duty to carry forward his visions – to turn India into a nation full of astro - ‘nomy’, not ‘logy’.
18
PHOTOGRAPHY SECTIONPHOTOGRAPHY SECTION
THE WEARY TRAVELER IS LYING ON THE ROAD AS HE WALKS, AND THE TREES ON THE ROAD ARE PEEKING AT HIM.
PHOTOGRAPHY BY : AKASH DEY
19
A GLIMPSE OF THE CITY OF JOY PHOTOGRAPHY BY : SUMIT BASAK
FIND THE PEACE PHOTOGRAPHY BY : SUMIT BASAK
20
SIR JOHN ANDERSON ROCK GARDEN, DARJEELING PHOTOGRAPHY BY : PUJA ADHIKARY
21
>> >> Q> > Q> > > > > \] > \] ? ? > > > >
\] Q> \] Q> Q> Q> ''-- ' ' Q> Q> , , ''--' ' ''>>' ' , , > >
n n \ \ 0 Q> 0 Q> \] > \] > > > > >
[ ]
--
( West Bengal, India )
22
> > \> > \ -- ] ]
]> > ]> > , , \] >\] > > > , , q q > > ] > ] > , , , , > > q >> > q > > > > > -87STS-87STS > >, , > > > > > Q > Q > > Q Q> Q> > > Q Q> Q> > >
, , > > ] > > ] > > 0 o ] 0 o ] > >
> >,, > >, , > > \ \ > > > 0 > Z> 0 > Z 0 0 , , > >
23
0 0 \ Q \ Q
0 Q> > 0 Q> > ''' ' ''' ' Q> > Q> > \ Q> > ‘’ \ Q> > ‘’ > 0 \>> 0 \> \ Q \ Q , , Q>Q> Q>Q> > > >q > > >q--_ _ > >, , \] \] > > ] > > > ] > > >
24
> 0 > 0 , , , , ^ 0 ^ 0 -- > > - - > > > > > > > > > T > > T > , , ,, \ \ \ \ , , > > - - > \ > \ > > ] > > ] Q> > Q> > , , > > 0 0 >> >> Carcinogen Carcinogen , , > 0 > 0 > 9 > 9 : : \ \ ,, o o, , >>, , , , 9 9 – – , , , , , , \ \ :: \ \ > > > > > > Q QQ Q : : Q Q Q Q , , 0 Q Q 0 Q Q 9 9 \ \ :: ª \ ª \ -- > >
, , Dr. Sankar Kumar NathDr. Sankar Kumar Nath
SENIOR ONCOLOGIST OF CULCUTTA MEDICAL COLLEGE, SENIOR ONCOLOGIST OF CULCUTTA MEDICAL COLLEGE, R.G. KAR MEDICAL COLLEGE AND BANKURA SAMMILANI R.G. KAR MEDICAL COLLEGE AND BANKURA SAMMILANI MEDICAL COLLEGE.MEDICAL COLLEGE.
MBBS, DMRT
25
:: Fungus Fungus -- > > T T :: :: , , CarcinogenCarcinogen > > > >, , > > , , > o> o > > > > , , ,, , , >>, , > >
, , 0 0 :: > Q> > Q>, , , , ,, > >,, Q> Q>, , , , , , , , , , >>,, >>, , > > -- :: , , , , > >> > >> ,, >> >> , , , , , , , , 0 0 33 -- :: >>, , , , , , , , , , ,, > >> >, , , , , , > >, , , , , , > > , ,
0 0 :: > > 3 3 Q Q \ \ > > > \ > > > \ > > \ > > \ > > -- \ \ 00, , Q>Q>, , Q> 9 Q> 9
:: > > > > > > > 0 > > 0 > > >
26
& ! ! &3 & ! ! &3, , & ! ! & / &3 & ! ! & / &3
& && &, , & & O3 >&& & O3 >&, , @ ! &3 @ ! &3 ,,
! > ! > ?? & ! & & ! && ! & & ! &, , > &> > &> '' & &''
''& & &&& & &&,, & & & &''
6> ! ! ! 6> ! ! !, , 6 && ! !6 && ! !
! ! 6! ! ! : ! ! 6! ! ! : O3> > @ ! /O3> > @ ! / > & > & , ,
& & ! ! > & & ! ! > > > ,,
O3> ! O3> !
( West Bengal, India )
27
, , , , Q > 9 Q > 9 99- - 9 9 ''--'- '- q q ''99' ' -- > 0 > > 0 > --
;; --> > > > ;; f f ’ 9’ 9
9 9 9 9 ''' (' ( > > , , ) ) ] ] ! ! _ 0 _ 0 9 9 9 9 ] ] > > >> >> , C, C = 4 = 4 -t-t 160. 160. Q Q >> = t = t ] ] C C ^ 99 ^ 99 ''' ' > 9 9 > 9 9 ? ? Q Q ] ] 40 40 Q Q 4.4 4.4 > 9 9 > 9 9
-- > >> >
( West Bengal, India ) TELESCOPES & OPTICS SPECIALISTTELESCOPES & OPTICS SPECIALIST
28
45 45 Q Q 7.2 7.2 > > 20 20 9 9 9 9 = 4 45 - 160 = 180 - 160 = 20. C x = 4 45 - 160 = 180 - 160 = 20. C x ] ] 70 70 Q Q 21.11 21.11 > 9 9> 9 9-- o > o > > 99 > 99 160 160 200, 200, ] ] ? ? > > 80 80 9090 Q Q > > > > 26.66 26.66 32.22 32.22 '' ' '
29
,, ,,
, ,
,, " # " #
( # # ( # #
- -,, - #- - #-
-/ # - # -/ # - # - -
- 4 " - - - 4 " - - - - " - - "
# #
( West Bengal, India )
30
The solar system is made up of Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The study of the data relating to each planet has allowed us to divide them into two groups: the terrestrial planets, or similar to Earth, (Mercury, Venus, Earth and Mars) and the jovian planets similar to Jupiter, (Jupiter, Saturn, Uranus and Neptune). The biggest difference that distinguishes these two groups is the size: the Jupiter planets are in fact larger and are also called giant planets. Due to the presence of the asteroid belt between Mars and Jupiter, the planets between the belt and the Sun are called inner planets, while those beyond the belt are called outer planets. Other differences between the planets are the composition, density and speed of rotation. While the density of terrestrial planets is about 5 times that of water, that of the Jupiter planets is around one and a half times. The materials that make up the various planets are of three types: gases, such as hydrogen and helium,
The solar systemThe solar system ( Bergamo, Italy )
By : Alexandra AlbaniBy : Alexandra Albani
31
rock-like materials such as silicate minerals and metallic iron, and ices which include ammonia, methane, carbon dioxide and water. The escape velocity is the velocity that a body must acquire in order to leave the atmosphere and therefore move away from the planet. The origin of the Solar System. Regarding the origin of the Solar System with the passage of time, a hypothesis called the nebular hypothesis has been formulated, according to which all the planets originated from a huge cloud of dust and gas, called the primordial nebula, formed by all those materials that we can find today on the planet of the system. Around 5 billion years ago this cloud of gas and heavy grains began to contract due to gravitational interactions and as this contraction took place, it kept increasing the speed of rotation according to the angular momentum principle. A moment came when the centrifugal force balanced the gravitational thrust towards the interior and the cloud turned into a flattened disk with a concentration of materials in the center that made up the protosole. Following the formation of this protosole, the phase of gravitational heating began, during which the temperature in the area of the inner planets began to decrease, favoring the aggregation of materials and the condensation of others, to give rise to planetesimals. Following the various collisions, the proto planets originated, which increased more and more to form what today are the 4 inner planets. Those aggregates of matter that did not form the planets remained in orbit between Mars and Jupiter and form what is now called the asteroid belt. Simultaneously with the formation of the inner planets there was that of the outer planets, which having lower temperature due to the greater distance from the sun, became an agglomeration of ices. Several satellites also formed around these outer planets.
The "dome" that surrounds us is called the celestial vault and has an apparent motion.Until 1600 it was thought
32
that there were 600 stars.From 1609, thanks to Galileo Galilei, the telescope began to be used.
LIGHT: it is an electromagnetic radiation that propagates with a wave motion. Electromagnetic waves have a crest and a belly, and are characterized by a wavelength (the distance between two crests or between two bellies) and a frequency.The shorter the wavelength, the higher the frequency.The information that comes from space travels in the form of electromagnetic waves and propagates both through the vacuum and through means transparent to them. To reach us, the light takes a time proportional to the distance at which the light source is located. The sunlight takes 8 minutes to arrive on our planet. In astronomy, to express the distances of celestial bodies, the light-year is used (the distance traveled in a year by light in a vacuum (9460 km). Stars and galaxies. Stars are celestial bodies within which a huge amount of energy that propagates in the universe.In the nucleus of the stars hydrogen is transformed into helium (4 hydrogen nuclei form 1 helium nucleus). The stars are very far away and hold their positions fixed. At the poles, all stars are circumpolar, meaning they make a complete rotation around the polar star. If a star rises and sets it is called occidua. The stars group together to form galaxies. Earth is part of the Milky Way (or Galaxy). It has a disc shape in which spiral arms can be seen, in one of which the Sun is located. Andromeda and the Magellanic Clouds are visible to the naked eye. Constellations are groupings of stars. There are 88 and they allow us to divide the universe into sectors. 12 are of the zodiac, and are on the plane of the earth's orbit.
33
The stars in a constellation are at enormous distances from each other. The brightest star in a constellation is called Alpha.The mass: from 0.02 to 200 times the mass of the sun. The dimensions: they vary from 0.1 to 1000 times the radius of the sun. The density: it can also be different The measurement of the surface temperature (on which the color of the star depends). The hottest stars are blue-blue-white, the coldest (3000-8000 ° C) red- orange-yellow. Brightness is measured by apparent magnitude. It depends on the amount of light emitted and the distance from the Earth. Sirius, for example, is brighter than the Sun, but further away. The solar system is a planetary system consisting of a variety of celestial bodies kept in orbit by the gravitational force of the Sun, which also includes the Earth: with a diameter of about 120-130 AU (if understood as the area of space that is subjected to the solar wind, leaving out the immense area subjected to solar gravity alone) is located in the Orion arm of the Milky Way, orbiting around the galactic center at a distance of 30000 al and a speed of 230 km / s; it is estimated that the solar system takes about 230 million years to complete one revolution around the galactic center.
Consisting of the Sun, which alone possesses 99.86% of the power of the entire system, and eight planets (four inner rocky planets and four outer gas giants) and five dwarf planets, their respective natural satellites, and many other bodies minor, the latter category includes asteroids, largely divided between two asteroid belts (the main belt and the Kuiper belt), comets (mainly located in the hypothetical Oort cloud), meteoroids and interplanetary dust.
34
In order of distance from the Sun, the eight planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune; the five dwarf planets are: Ceres, located in the main asteroid belt, Pluto, Haumea, Makemake, and Eris. The solar wind, a flow of plasma generated by the continuous expansion of the solar corona, permeates the entire solar system, creating a bubble in the interstellar medium known as the heliosphere, which extends beyond half of the diffuse disk. celestials of the solar system were already known since ancient times, the concept itself was ignored as there was mostly an idea of a geocentric system with the Earth at the center of the universe. One of the first to imagine a heliocentric system was Aristarchus of Samo, but his ideas did not take hold in the community of philosophers and thinkers of the time.
It was only in the sixteenth century that Nicolaus Copernicus proposed the modern vision of the solar system, with the Sun at the center and the planets known at the time to orbit around. The only known bodies in the solar system, however, were only the four terrestrial planets, Jupiter, Saturn, the Sun and the Moon. In the following century, with the invention of Galileo Galilei's telescope, other minor bodies were discovered, such as the Medici satellites, the rings of Saturn and some comets and for about 200 years it was not thought that there could be other objects in the solar system, in particular was the firm belief that the planets were only those then known. In 1781, the discovery of Uranus by William Hersche questioned the preconceptions that the scientific community had, generating doubts regarding the possibility that transuranic planets existed.
A few years later, in 1801, Giuseppe Piazzi declared that he had discovered a new planet, between the orbits of Mars and Jupiter; it was actually Ceres. The conclusion came by excluding that it could be a comet and not
35
knowing other objects other than planets and comets, completely unaware that he had discovered a new type of object, the asteroid. Since then the discoveries of new objects multiplied, in particular many new asteroids were discovered. In 1846 a planet was discovered in a completely revolutionary way: before direct observation, the perturbations of the orbit of Uranus were calculated and it was deduced that a planet had to exist at a precise point in space to justify the discrepancies observed. A few days later, Johann Gottfried Galle and Heinrich Louis d'Arrest confirmed the presence of Neptune less than one degree away from the calculated point.
In 1930, the discovery of Pluto increased the number of known planets to nine, which was then believed to be an object of much greater mass than it actually is. In the 1950s Jan Oort hypothesized the existence of a nursery of comets far beyond the orbits of known planets, located tens of thousands of AU from the Sun, the Oort cloud, which when disturbed significantly changed their orbit up to to arrive in the internal area of the system. In 1992, the discovery of Albion restarted the search for trans- Neptunian objects. The advent of automatic search systems allowed the discovery of thousands of objects with a diameter between 50 and 2500 km. The discovery of Eris, similar in size to Pluto, in 2005 challenged the very definition of planet, which was changed and formalized in 2006 by the International Astronomical Union, downgrading Pluto to a dwarf planet and bringing the total number of planets back to eight. The most accredited theories on the formation of the solar system describe its birth 4.6 billion years ago starting from the fragmentation and gravitational collapse of a gigantic molecular cloud with a diameter of 65 light years.One of these fragments, with an initial size of 2000-20000 astronomical units, collapsed into what is known as the protoplanetary disk. The main components of this primordial forge were 98% primo.
36
37
