Astronomy Look in to the night sky Several questions may come to your mind. How many stars are there in the sky ? What is the size of star ? Do all stars are having same size ? All astral bodies are stars only? What is/ are difference/s between stars and planets ? What is milky way ? Can we observe other Galaxies? The stars we observe by normal eyes are from our Galaxy only ? What is the length of our Galaxy? Which is the nearest star ? From different part of earth, the sky observations are same ? Our ancestors, i.e. Ancient Indians were aware of many facts about the universe in those days which other people in the world rarely aware at that time. Spherical earth, without support in sky etc. references are found in Vedas Constellations are explained but Sun-signs are not found in Vedas Pitamah Siddhant Soory Siddhant Romak Siddhant developed from 5 century BC to AD Aaryabhatt. VarahMihir, Brahmagupta, Munjal, Shatanand, Bhaskaraachary, Ganeshdaivadny were great astronomers. To understand this universe, we need some of the basics of Science. Universe is made up of Matter and energy. Matter is scattered in the universe in form of Galaxies. Energy is available in various forms like light, kinetic, heat etc. Minimum possible temperature in this universe is -273 degree Celsius. This is called as absolute zero. On Kelvin scale this temperature is considered as Zero Kelvin. Matter with temperature Zero Kelvin not emit any radiation and called as a dark matter. It is not black hole. Universe is having about 27% dark matter. Simplest atom is Hydrogen. Having One proton and one electron revolving around it. By fusion reaction hydrogen is converted into Helium. In this process mass is lost, i.e. converted to energy which is tremendous. This is the key factor of energy production of a star. Thus Hydrogen is converted to Helium, Helium is converted to Carbon and so on till Iron is formed. Last element formed in this reaction on star is 26Fe56. We are finding out answers of these questions in these lectures. This lecture is delivered by Prof. Mahesh Kulkarni who is in-charge of Savarkar IAS Study circle, Swatantryaveer Savarkar Rashtriya Smarak, Swatantryaveer Savarkar Marg, Chhatrapati Shivaji Maharaj Park, Dadar west , Mumbai 400 028. For details please call 9221849650
