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'We Will Succeed But...' Former ISRO Dy Director Dasgupta On Chandrayaan-3 Landing

Dasgupta while speaking stated that landing is a difficult task because there are many things that are yet to be known by the scientists. 

| Written By
Isha Bhandari

Image: X (Twitter)

Arup Dasgupta, former deputy director of ISRO while speaking to Republic Media Network touched on the significance of the Moon mission ahead of the expected touchdown of Chandrayaan-3 mission’s lander module on the surface of the Moon. Dasgupta shed light on the mechanism of the landing process on the Moon, the Luna-25 spacecraft crash, and the impact of the soft landing. “There is a hope that we will succeed but let me tell you this once again every space scientist knows that space is very very unforgiving,” he said. 

Mechanism of landing process on the Moon 

Dasgupta stated that landing is a difficult task because many things are yet to be known by scientists. 

"Yes, landing on the moon is a difficult task, because we need to know more about the moon. Nevertheless, when you are operating a spacecraft out there on the moon, all the communication with it is just through the communication links. If anything happens you have precious time to do the corrections. Therefore, the craft has to be more or less autonomous. If you look at the landing it starts about 15 mins before the touchdown, and that's when it is in an orbit which is roughly 30 km which is the closest to the moon and 100 km farthest from the moon. Now at that level, it starts doing what is known as a breaking manoeuvre. And there are 8 steps, which need to be taken as you reach the surface of the moon. At that stage, you try to come down from 30 km to about 7.4 km. The orbit is highly electric, and the speed of the craft is roughly about 6000 km per hour and has to be reduced to 1200 km per hour. To do that, you have to fire the thruster, in the direction in which the spacecraft is travelling. Then comes stage 2, where we travel from 7.4 km to about 6.8 km. At 6.8 km, first, all the systems are checked out. Now, what happens from 6.8 km it is coming down to 800 metres. The speed is further reduced when it comes to 150 km at that point the Chandrayaan is hanging at the top of the moon. There's a camera on board, which looks at the hazards of landing, if found any, it finds a good place to land.”

Luna-25 spacecraft crash regrettable

Speaking on Russia’s Luna-25 spacecraft crashed into the Moon after it spun into an uncontrolled orbit, the former deputy director of ISRO said, “The incident was very regrettable.” 

“The Luna 25 accident is very regrettable. Because any attempt in space is very unrelenting. Make the slightest mistake you are going to land up in trouble perhaps that's what happened to Luna. When the command was given for it to start descending then, the thrust was a bit too high. In the case of Chandrayaan-2, a similar thing happened, there was a lot of error built up there and the control system on board could not handle that much error because of this it couldn't follow the path and got destroyed. And yes, these kinds of things do play on the mind of engineers. May it be checking, or rechecking, the status of the lander. The spacecraft software has been updated to avoid such mistakes after studying the failure of Chandrayaan-2. So there is a hope that we will succeed but let me tell you once again that every space scientist knows that space is very very unforgiving. Despite your best efforts, things can go out of hand because there are many unknown factors which we haven't learnt yet.”

Arup Dasgupta on the impact of soft landing

Speaking on the impact of soft landing on Chandrayaan-3, Dasgupta said, “There are many entrepreneurs in India who are concentrating more on the land-based applications and are capable of doing it. If this landing is a success, I am sure that the private industry is going to expand. Not only in India but they'll make waves in the global market as well. We have a 2% share of the market, with this success we can bring it to 10%.” 

Notably, Chandrayaan-3, the third edition of the Moon mission series, if lands successfully on the lunar surface’s south pole will make India the first country to do so and the fourth country after the US, China, and the former Soviet Union to ever land on the Moon’s surface. 

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