Astronomy is the study of celestial objects, their motions, their positions, and properties. It is considered as oldest science after medicine. The clear starry night has always amazed humans.

The presence of astronomy in India can be seen since prehistoric times. Earlier it was used to predict auspicious dates for special events and religious festivals.

The beginning of astronomy can be traced back to Vedas- Rigveda and Yajurveda. Earlier astronomy was called Jyotisha. The Vedangna Jyotisa is the earliest available Indian Astronomy textbook. The accepted period for this book is between 12^th and 14^th century B.C. In today’s world, the word Jyotisha is used for predictive astrology or pseudo-science. But still it must deal with Sun, moons, planets, nakshatras, etc.  Have you ever wondered, how astrology books claim to predict positions of celestial bodies?

Mathematics was always a part of Jyotisa, which calculated the positions of celestial bodies in Vedic period. But it’s over utilization for religious predictions, hindered its development as science and became obsolete to modern world.

Vedanga Jyotisa 

Vedanga Jyotisa contains the record of essential astronomical knowledge needed by the people of Ancient India for day to day life. This book has two parts-

1.   Rigveda Jyotisa- This contains 36 verses.
2.   Yajurveda Jyotisa- This contains 44 verses.

The people of that era had good knowledge of planetary systems and some other celestial bodies. The planet Jupiter is mentioned as Brihaspati, Venus as Sukra or Vena in Rigveda. Apart from this, the sidereal period of moon, 27.3 days was well known during those days.

This book contains details of Nakshatras (Stars) and its groups (constellations). The brightest star in its group ware called as Nakshatras. The Rigveda Samhita mentions five Nakshatras and the Taittiriya Samhita mentions all 28 Nakshatras including Abhijit (Vega).

In vedanga Jyotisa, the calendarial items like seasons, solstices, the visuvas (equinoxes), the revolution of Sun and Moon as observed from earth, the length of longest day and the shortest night, etc is mentioned in detail.

Later on, Siddhantas or established theories were developed which were used for astronomical studies. At this time period, decimal system was introduced in Mathematics which helped astronomers to make precise calculations of celestial phenomenon.

In India, there were 18 well established Siddhantas- Surya, Paitamaha, Vyasa, Vasistha, Atri, Parasara, Kasyapa, Narada, Gargyan, Marici, Manu, Angira, Lomasa, Paulisa, Cyavana, Yavana, Bhrgu and Saunaka.

Power Transmission is the link of electricity supply from Generating Stations to its consumption point. This is often described as transmission network due to presence of interconnected lines with multiple Step up and Step-Down sub Station Units.

Transmission Lines carry high voltage electricity in the form of Alternating as well as Direct current. It can be a three-phase alternating current power transmission line or a single phase as in railway electric supply lines.

There are two types of power transmission system based on modes of transmission-

1.    Overhead Transmission System: -

 In overhead Transmission System, high voltage electric current is transferred through ground-based towers and line networks. This is the most common mode of power transmission due to its low erection cost and easy maintenance. This network is so widespread that you will find it in almost every cities, towns, and rural areas.

      2)  Underground Transmission System: -

The underground cables are not exposed to outdoor weather conditions. So once installed it has longer life and requires very less maintenance. There are several types of cables used in underground transmission system depending on its type of usage. Normal XLPE and dielectric liquid filled cables are used for short distances. But HVDC cables are heavy duty cables used for very long distances.

Underground Transmission system has limited use due to lack of its ability to upgrade and very hard fault location and its repair.

 The power transmission Systems are classified into two, based on voltage levels of transmission-

                 1)     Primary transmission: -

At Generating Stations, the electricity generated is at a voltage level of 6 KV to 11 KV at 50 Hz.  This voltage is not ideal for transmitting to distribution networks due to losses over long distances . So, electricity generated at Generating Stations are sent to a Step-Up Power Unit through transmission lines. The step-up voltages can be 66 KV, 132 KV, 765 KV or 1000 KV depending on distance of transmission.  The transmission lines carrying one of these step-up voltages terminate at a step-down power unit where voltages are converted to 132 KV or 66 KV. This is primary transmission in power system.

2)     Secondary Transmission: -

The secondary transmission lines emerge from receiving ends of primary transmission lines and connect to distribution systems. The voltage is further step down from 132 KV or 66 KV to 33 KV or 11 KV.

1. Technical Losses
2. Commercial Losses

Please visit this link for details on AT & C Losses:- https://electricalessence.blogspot.com/2017/10/what-is-at-c-losses_29.html

Several projects have been carried out to reduce AT & C Losses in India. And these have succeeded in reducing AT & C Loss from 35% (2004-5) to 18% (2019-20).

Technical Loss Reduction

Technical losses occur in electricity supply through the distribution system network. It consists of transformers, conductors, switchgears and cables. It occurs due to transformation of different voltage levels and I2R loss in conductors.

To overcome this technical loss-

• Regular maintenance of feeders and transformers are done.
• To overcome overloading, separate feeders were made for domestic and commercial consumers.
• To reduce lengths of feeders, separate feeders were made for Irrigation and domestic use.
• Replacement of switchgears at sub-stations was done along with bay extension.
• Technically Advanced sub Stations were built in high demand areas.
• High Voltage Distribution System (HVDS) was introduced in areas of high theft.
• AB Cabling for bare conductor replacement.

AB Cabling in Rural Area

Projects launched by Govt. of India to reduce technical losses are-

1. Rajeev Gandhi Grameen Vidyut Karan Yogna (RGGVY), year-2005.
2. Backward Region Grant Fund (BRGF), Year-2007.
3. Restructured Accelerated Power Development & Reforms Program (R-APDRP), Year-2008.
4. Integrated Power Development Scheme (IPDS), Year-2015.
5. Deen Dayal Upadhaya Gram Jyoti Yogna (DDUGJY), Year-2015.

Commercial Loss Reduction

Commercial loss is the loss of revenue which should have been acquired for electricity supply. It is mainly due to obsolete metering technology, non-realization of electricity bills and theft.

To overcome commercial loss-

• Consumer Indexing must be done.
• Installation of smart meters (in Rural Areas) and pre-paid meters (in Urban Areas) in 100% consumer premises.
• Regular 100% Billing Efficiency.

         Billing Efficiency= (Total Units Sold or Billed in Kwh/Total input energy in Kwh)*100

• Improvement in Collection Efficiency.

         Collection Efficiency= (Total revenue from consumers/Total billed amount to consumers)*100.

• Strict rules implementation on electricity theft and hooking on conductor.

Projects launched by Govt. of India to reduce commercial losses are-

1. Saubhagya Yojna, Year- 2017.
2. Smart Metering projects, Year- 2016.
3. Billing Through RRFs Model and Agency Model.
4. Uday Scheme, Year-2015.

Asia’s Largest Reflector

 Telescope- DOT

The Aryabhatta Research Institute of Observational Sciences (ARIES) built a 3.6-meter reflector telescope (Devashtal Optical Telescope), is the largest reflector telescope in Asia. It is located at Devasthal site 30 Km from Nanital India. Its construction was completed in 2015 and was activated remotely on 31^st March 2016 by Indian Prime minister Mr. Narendra Modi and Belgian Prime minister Mr. Charles Michal.

This telescope is first of its kind in India with three features-

• High resolution Steller Spectro polarimeter
• Charged Coupled device (CCD) Imager
• Near Infra-red Spectrograph

It has active optic system, a wave front sensor, and pneumatic actuators for compensating micro distortions. This is controlled remotely from Bangalore for observing-

1. Magnetic Field Structure of stars
2. Search for planets
3. Chemical composition of Milky way galaxy
4. NIR Spectroscopy and narrow band imaging of galactic nuclei and debris around stars.
5. Optical spectroscopy and high resolved imaging of Binary systems.

Thank You

IRSO Launched Free Online Courses- Get Enrolled

ISRO has launched free online courses through IIRS-ISRO Outreach Program. This program focuses on developing concepts of Space Technology and Its Application.

The Indian Institute of Remote Sensing (IIRS) runs the online program in two modes-

• Ø  Live and Interactive (EDUSAT) Courses.
• Ø  Lerner Centric E-Learning Courses.

The IIRS is going to provide three different online courses in this month which is free-

1.   Global Navigation Satellite System (Starting on 14^th September,2020).
2.   Understanding of Coastal Ocean Processes using Remote Sensing and Numerical Modelling (Starting on 21^st September,2020).
3.  Geographical Information System (Starting on 28^th September,2020).

These courses can be streamed only through Internet Explorer or Mozilla Firefox.

Live and Interactive Mode

For Live and Interactive Mode, your School, College, University or Organization must be registered on this platform. These can be registered following these steps-

1.    Go to IIRS website- https://elearning.iirs.gov.in
2.    Click on Register for Program.
3.    In drop down menu select Live and Interactive Program.
4.    Select Register your Institute.

      

1. Register yourself.

2) Click on YES/NO and Submit.

3)Fill the required details and submit.

Thank You

AstroSat was launched on September 28, 2015 using PSLV launch vehicle by Indian Space Research Organization (ISRO). It is first Indian Astronomical satellite dedicated for studying deep sky celestial objects using multi wavelength analysis simultaneously. It can observe X-Ray (like Chandra X-Ray Observatory), Optical (like Hubble Telescope) and UV bands simultaneously.

Its primary objective is to observe high energy processes in binary star systems, estimate magnetic fields of neuron star, detect new briefly bright X-Rays and perform deep sky observations in Ultraviolet region.

The minimum useful life of AstroSat is of 5 Years. During this lifespan it is controlled by a ground-based control station of ISRO located at Bangalore.

In recent update from ISRO about AstroSat Mission is that it discovered a deepest galaxy which was named as AUDFs01.It is estimated to be 9.30 billion light-years away. This discovery was made by observing Extreme Ultraviolet Light coming from other galaxy by scientist at Inter-University Center for Astronomy and Astrophysics (IUCAA), Pune.

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In simple terms, GDP is the estimated value of Goods and services produced in a country for a particular time frame. We can say that the economic growth of a country directly depends on its GDP. Higher the GDP, higher is its economic growth.

In this COVID-19 pandemic time GDP of this country is continuously decreasing. This leads to slow economic growth & decreased per ca pita income. So, we must understand how GDP is related to Economic growth contribution of common man in it. Let me explain with an example.

I am a private sector employee. Before pandemic, my overall monthly expenditure was Rs 25000. This was my indirect investment in the market. My expenditure was in form of paying rent, bills, outdoor dining, movie theater, snacks & tea shops, regular consumable goods, vehicle fuel, outdoor hangout with friends, etc. But now I am leaving in this pandemic time. My overall expenditure was cut short to around Rs 18000. Now this is my indirect investment in the market. As we all are aware of the reason. Due to pandemic I must close my outdoor activities like outdoor dining, hangout with friends, movie theater, vehicle fuel, etc. This leads to no investment on these activities. In a way I saved Rs 7000 but in other way, market lost Rs 7000. This is loss of 28 percent of my expenditure for market.

Taking consideration of the entire population of this country, the loss for market is too huge. The less investment by people leads to low demand of goods which in result depreciates the production.

Now a company with low production will require lower number of employees. Thus, few or more employees will be fired leading to no source of stable income for some of them. This on exponential condition will lead to recession.

A common man contribution to market has huge impact on GDP and economic growth of a country.

Thanks