Science Horizon Volume 5 Issue 7 July, 2020 President, Odisha Bigyan Academy Editorial Board Prof. Pramod Chandra Mishra Prof. Niranjan Barik Editor Prof. Ramesh Chandra Parida Er. Mayadhar Swain Dr. Choudhury Satyabrata Nanda Managing Editor Dr. Rajballav Mohanty Er. Bhagat Charan Mohanty Secretary, Odisha Bigyan Academy Dr. Nilambar Biswal CONTENTS Subject Author Page 1. Editorial : Hubble at 30 Er. Mayadhar Swain 2 2. The Mysterious Concept of mass - I Dr. Bijay Kumar Parida 4 3. Disinfectants Dr. Manas Ranjan Senapati 9 4. Tricks of Trigonometry Birendra Kumar Acharya 11 5. Policy Issues on Global Warming and Climate Change Dr. Bijay Ketan Patnaik 13 6. Mahendragiri- The Lesser Known Natural Heritage Dr. Sundara Narayana Patro 18 Site on Eastern Ghats 7. Coronavirus and Herd Immunity Basanta Kumar Choudhury 23 8. Viruses Exist in a Gray Area between Chemistry Dr. Dwijesh Kumar Panda 26 and Life 9. Locust Menace Dr. Taranisen Panda 28 Dr. Raj Ballav Mohanty 10. Science of Yoga Dr. Choudhury Satyabrata Nanda34 11. Hepatitis B: A Serious Killer Prof. Prafulla Kumar Mohanty 38 12. Lise Meitner and Otto Hahn- Part II B. Sahoo 41 (The Discovery of Nuclear Fission) H.C. Rai Dr. P.K. Pujapanda 13. Quiz: Covid 19 Birat Raja Padhan 46 14. Recent News on Science & Technology 47 Cover Design : Kalakar Sahoo JULY, 2020 // EDITORIAL // HUBBLE AT 30 Since the launch of the first satellite HST was launched on 24 April, 1990 Sputnik 1 to the space in 1957, many countries along with Space Shuttle Discovery mission have sent a number of satellites and spacecrafts STS-31 and released to Earth’s orbit next day. to the space. Although they are serving a lot of HST was the first spacecraft designed to be purposes for the mankind, their initial and maintained, upgraded and repaired by astronauts main aim was to explore the vast worlds outside while still in space. Over the years, there had our Earth and acquire knowledge about the been five service missions all staged from the Universe. The one spacecraft which has served Space Shuttle. The astronauts had to go outside us marvellously in this direction is Hubble the shuttle, do space walk and repair or modify Space Telescope (HST). It is a rotating telescope the HST before coming back to their vehicle. in the Earth’s orbit. It is located at a height of During service missions, astronauts replaced 547 km above Earth’s surface and takes 97 solar arrays, four gyroscopes, two minutes to rotate once around the Earth. magnetometers and electrical components and The idea of putting a telescope in space they also upgraded the onboard computers. was first suggested by Hermann Oberth, a Initially HST had five scientific instruments German rocket scientist way back in 1923. such as Wide Field and Planetary Camera The idea was to avoid the distortion faced by (WFPC), Goddard High Resolution the terrestrial telescopes from Earth’s Spectrograph (GHRS), High Speed atmosphere. After the space age started with Photometer (HSP), Faint Object Camera the launching of satellites in 1950s, NASA (FOC) and Faint Object Spectrograph (FOS). considered the proposal of launching telescopes In 2009, Wide Field Camera 3 (WFC3) and to the Earth’s orbit. HST is one of them. Cosmic Origins Spectrograph (COS) were HST has been named after a great installed and a Soft Capture Mechanism (SCM) astronomer of USA, Edwin Powell Hubble was put in. (1889-1953) who had discovered the expansion HST is known as people’s telescope for of the Universe while working at Mount Wilson the pioneering science and space investigation Observatory. He observed that the distant galaxies carried out by it, which enhanced our are moving away from us and the velocity of knowledge on cosmology. During the last three such galaxies was proportional to their distance decades, it has given us marvellous pictures of from the Earth. This was the first evidence of astronomical bodies and events. In 1994 when the expansion of the Universe. He also calculated comet Shoemaker Levy 9 collided with Jupiter, relationship of galaxies’ velocities and their it sent us the images of the comet before and distance from us, which is now known as ‘Hubble after the impact. It showed how the comet was Constant’. Of course one of HST’s primary broken into many pieces due to gravitation of missions was to refine the Hubble Constant. Jupiter before the impact. It has found jets of 2 Science Horizon JULY, 2020 water vapour erupting on the surface of is assumed to make up about 75 percent of the Jupiter’s moon, Europa and from its image it entire known Universe. is now assumed that there is a 100 km – deep HST has taken deep images of evolution subsurface ocean beneath the 150 km ice of over 250,000 galaxies, exploring the crust of Ganymede, the largest moon of Jupiter. evolution of early Universe from less than a It took pictures of collision of two asteroids billion years after the Big Bang. In 2016, it and disintegration of another asteroid. discovered the oldest and the farthest known HST discovered Pluto’s moon Styx, galaxy, GN-z11, which is 32 billion light years Hydra and Nix and in 2015 located five new away. It has sent us images of the formation of Kuiper belt objects when it was used to find a new stars thereby enhancing our knowledge of target for the New Horizons mission. In 2001, planetary formation. it detected the elements present in the HST has detected a supernova in a distant atmosphere of the exoplanet HD 209458b and galaxy and it has also caught images of merger in 2008 it took the first ever visual image of of galaxies. It has taken marvellous pictures an exoplanet Formalhaut b. It was the first of nebulae, the most famous being one of the telescope to determine the first colour of an birthing grounds of the Eagle Nebula, M16. exoplanet. It also discovered water vapour in The picture, taken in 1995, is better known as the atmosphere above exoplanet K2 – 18b for the Pillars of Creation (shown on the back the first time. cover of the magazine) inside which new stars From the data of HST, the size and mass are beginning to form. of our Milky Way Galaxy, and the rate of In 2019, HST found a gamma ray burst expansion of the Universe were calculated. (GRB) coming from dense environment of a From this data, the age of the Universe is very bright galaxy around 5 billion light years calculated to be 13.7 billion years. From its away. GRBs are the most powerful explosions data in 1998, astronomers could know that the in the Universe, but their origins are not light coming from the most distant exploding known yet. stars was fainter and more stretched (red- No other space mission has enlightened shifted) than predicted. It meant that they were us as HST. Many of its images have been further away than calculated earlier. This was cultural icons appearing not only in science against idea that the expansion of the Universe books and magazines, but also in albums and was slowing down due to gravity. From its data, even in coffee mugs. For the last thirty years, it was clear that the Universe is accelerating it has been working productively and it is more than was expected earlier. expected that it would work well up to 2040. From this astronomers came to the HST will soon be joined by the James Webb conclusion that to overcome the gravity, Space Telescope and working in conjunction something must be giving an opposite and with each other they will continue to survey repulsive force as the Universe expands and the cosmos. matter is spread out. This mysterious ‘something’ is dubbed as ‘dark energy’ which Er. Mayadhar Swain Editor Science Horizon 3 JULY, 2020 THE MYSTERIOUSCONCEPT OF MASS – I Dr. Bijay Kumar Parida Introduction particle with zero mass (such as photon) to When a student was asked, “What is your our universe with a mass of the order of 52 mass?” the student fumbled with the answer. 3×10 kg. But when asked, “What is your weight?” prompt Students of science know that mass is a came the answer: “30 kg”. This dialogue fundamental concept from which that of weight indicates two things which are found not just is derived. Apart from this the concept of with young learners but with adults as well. mass has many aspects some of which are not First: our concept of mass is not clear. well understood even today. This makes mass Second: we wrongly use kg as the unit of a mysterious concept of science. In this article weight. Students in secondary classes know we shall try to touch upon the various aspects that kg or kilogram is the SI unit of mass of mass without going into the technical whereas that of weight is N or, newton or, kg details. For the benefit of students, we shall m s-2. give a few simple numerical examples and From everyday handling of objects, we exercises. In our presentation we shall include happen to be more familiar with the concept some well-known and some less-known facts of heaviness (a measure of weight) than the about mass. As it is not possible to cover all concept of mass. This is because it is easier to of them in a few pages, we propose to discuss feel the weight of objects through the efforts them in several parts of an article, beginning we need to make to lift or move them.