 space, a mysterious thing, right? It is always beyond the imaginations of the human beings and what can we do about it other than admiring at it, gazing at the stars and wondering what they are made of and finally hoping that we'll also get an opportunity to go there and see for ourselves what they are made of and what wonders it holds that makes it so attractive and catchy. If you also want to go to space, you should know at least one thing about the launch vehicle that sends you to space, right? And here's about the launch vehicle that is going to send you to space. See, yesterday ISRO chairman announced that ISRO is developing a next generation launch vehicle and this will replace Polar satellite launch vehicle PSLV See, the chairman also said that NGLV that is the next generation launch vehicle will use semi cryogenic technology. See, it is both efficient and cost effective and he also highlighted that the new rocket could also be reusable. See, if it is made reusable, it is going to have a smaller payload that would be around 5 tons and also if the rocket is made expendable, the payload capacity will also further go up to 10 tons. Now using this opportunity, we are going to learn about the differences between Polar satellite launch vehicle PSLV and Geosynchronous satellite launch vehicle GSLV. Now the first difference is based on the generation. See, PSLV is the third generation satellite launch vehicle of India whereas GSLV is the fourth generation satellite launch vehicle of India. Now you may wonder, then what is the first and second generation launch vehicles? See, they are satellite launch vehicle SLV and augmented satellite launch vehicle ASLV respectively. Now moving on to the next difference. Now this difference is based on the orbits and their use. See, PSLV has earned the title of work horse of ISRO. See, this is because of its consistent delivery of various satellites to low earth orbits. See, this is a gentle term. If the altitude of the orbit is low from the earth, then it is called as low earth orbits. It may range from 200 kilometers to 1600 kilometers and also know that PSLV is designed to deliver the earth observation or remote sensing satellites to sun synchronous circular polar orbits of 600 kilometer altitude. Now coming to GSLV. See, GSLV is designated mainly to deliver the communication satellites to the highly elliptical geosynchronous transfer orbit. This is the major difference. Now moving on to the next difference. Now this is based on the stages of the launch vehicle. First, let us see the PSLV. See, PSLV is a four stage launch vehicle with the first and third stages using solid rocket motors and the second and fourth stages using liquid rocket engines. And also know that PSLV uses six strap on motors to augment the thrust provided by the first stage. Here you have to note that depending on the number of the strap on boosters, the PSLV is classified into various versions like core alone version, PSLV CA, PSLV G and PSLV XL etc. See, these strap on motors and boosters, they will be mounted on the sides of the launch vehicle. Now coming to the GSLV. See, GSLV has three stages. The first stage uses a solid rocket motor, then the second stage uses a liquid rocket engine and the third stage uses the indigenously built cryogenic engine. See, the cryogenic engine carries liquid hydrogen as fuel and liquid oxygen as oxidizer. We all know why oxidizer is used, right? Because there will be no oxygen in the space. But for combustion to occur, we need oxygen and that is exactly why oxidizers are used. Now here also, GSLV uses four liquid engines strap on motors for the thrust. And there are different variants of GSLV launch vehicles based on the lift off capacity. They are GSLV Mark 1, GSLV Mark 2 and GSLV Mark 3. Now these are the three main differences between PSLV and GSLV. See, each and every point that we discussed today, they are very important for your examination. It will be useful for your problems as well as your mains. Have you all read the 2022 mains question paper? If you did, then you know that many questions have been asked which are related to statics. So it is always good to have your foundation strong. Only if you are very strong in your statics, then only you will be able to understand the current affairs. Especially when it comes to science-related current affairs, you have to have a base. So make note of all of the points that we discussed today. If you want to know more about the science-related topics and the current affairs related to it, follow the Hindi News Analysis of Shankarae's Academy. Thank you.