“We chose the second option. We reduced the number of thrusters from 16 to eight and the pressure tanks and batteries were reduced from two to one.

According to Mr Annadurai, the reduction in the number of batteries meant that the launch had to take place before the end of 2008.

“This would give the spacecraft two years to circle the Moon without encountering a long solar eclipse, which would impact its ability to recharge. So we had to maintain a strict work schedule to meet the launch deadline.

Mangalyaan cost so little, Mr. Annadurai says, “because we used most of the hardware we had already designed for Chandrayaan-2 after the second lunar mission was delayed.”

Mr. Bagla believes that India’s space program, achieved at such a low cost, is “an incredible feat.” But as India grows, the cost could rise.

Right now, he says, India uses small rocket launchers because it doesn’t have anything more powerful. But this means that Indian spacecraft take much longer to reach their destination.

So when Chandrayaan-3 was launched, it circled the Earth several times before being launched into lunar orbit, where it circled the Moon several times before landing. On the other hand, the Russian Luna-25 quickly escaped Earth’s gravity thanks to a powerful Soyuz rocket.

“We used Mother Earth’s gravity to push us towards the Moon. It took us weeks and a lot of ingenious planning. Isro has mastered this and has done it successfully on many occasions.

But, according to Mr. Bagla, India has announced its intention to send a manned mission to the Moon by 2040. and it would take a more powerful rocket to get the astronauts there more quickly.

The government recently said, external work on this new rocket had already been approved and it would be ready by 2032. This next generation launch vehicle (NGLV) will be able to carry more weight but will also cost more.

Furthermore, Bagla says, India is opening up the space sector to private players and costs are unlikely to stay that low once that happens.

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