Why it costs India so little to reach the Moon and Mars

India recently announced a host of ambitious space projects and approved 227bn rupees ($2.7bn; £2.1bn) for them.

The plans include the next phase of India’s historic mission to the Moon, sending an orbiter to Venus, building of the first phase of the country’s maiden space station and development of a new reusable heavy-lifting rocket to launch satellites.

It's the single largest allocation of funds ever for space projects in India, but considering the scale and complexity of the projects, they are far from lavish and have once again brought into focus the cost-effectiveness of India’s space programme.

Experts around the world have marvelled at how little Indian Space Research Organisation’s (Isro) Moon, Mars and solar missions have cost. India spent $74m on the Mars orbiter Mangalyaan and $75m on last year’s historic Chandrayaan-3 – less than the $100m spent on the sci-fi thriller Gravity.

Nasa’s Maven orbiter had cost $582m and Russia’s Luna-25, which crashed on to the Moon’s surface two days before Chandrayaan-3’s landing, had cost 12.6bn roubles ($133m).

Despite the low cost, scientists say India is punching much above its weight by aiming to do valuable work.

Chandrayaan-1 was the first to confirm the presence of water in lunar soil and Mangalyaan carried a payload to study methane in the atmosphere of Mars. Images and data sent by Chandrayaan-3 are being looked at with great interest by space enthusiasts around the world.

So how does India keep the costs so low?

Retired civil servant Sisir Kumar Das, who looked after Isro’s finances for more than two decades, says the frugality can be traced back to the 1960s, when scientists first pitched a space programme to the government.

India had gained independence from British colonial rule only in 1947 and the country was struggling to feed its population and build enough schools and hospitals.

“Isro’s founder and scientist Vikram Sarabhai had to convince the government that a space programme was not just a sophisticated luxury that had no place in a poor country like India. He explained that satellites could help India serve its citizens better,” Mr Das told the BBC.

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But India’s space programme has always had to work with a tight budget in a country with conflicting needs and demands. Photographs from the 1960s and 70s show scientists carrying rockets and satellites on cycles or even a bullock cart.

Decades later and after several successful interplanetary missions, Isro’s budget remains modest. This year, India’s budgetary allocation for its space programme is 130bn rupees ($1.55bn) - Nasa’s budget for the year is $25bn.

Mr Das says one of the main reasons why Isro’s missions are so cheap is the fact that all its technology is home-grown and machines are manufactured in India.

In 1974, after Delhi conducted its first nuclear test and the West imposed an embargo, banning transfer of technology to India, the restrictions were “turned into a blessing in disguise” for the space programme, he adds.

“Our scientists used it as an incentive to develop their own technology. All the equipment they needed was manufactured indigenously - and the salaries and cost of labour were decidedly less here than in the US or Europe.”

Science writer Pallava Bagla says that unlike Isro, Nasa outsources satellite manufacturing to private companies and also takes out insurance for its missions, which add to their costs.

“Also, unlike Nasa, India doesn't do engineering models which are used for testing a project before the actual launch. We do only a single model and it's meant to fly. It's risky, there are chances of crash, but that's the risk we take. And we are able to take it because it’s a government programme.”

Mylswamy Annadurai, chief of India’s first and second Moon missions and Mars mission, told the BBC that Isro employs far fewer people and pays lower salaries, which makes Indian projects competitive.

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He says he “led small dedicated teams of less than 10 and people often worked extended hours without any overtime payments” because they were so passionate about what they did.

The tight budget for the projects, he said, sometimes sent them back to the drawing board, allowed them to think out of the box and led to new innovations.

“For Chandrayaan-1, the allocated budget was $89m and that was okay for the original configuration. But subsequently, it was decided that the spacecraft would carry a Moon impact probe which meant an additional 35kg.”

Scientists had two choices - use a heavier rocket to carry the mission, but that would cost more, or remove some of the hardware to lighten the load.

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

Reducing the number of batteries, Mr Annadurai says, meant the launch had to take place before the end of 2008.

“That would give the spacecraft two years while it went around 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 Moon mission got delayed”.

Mr Bagla says India’s space programme coming at such low cost is “an amazing feat”. But as India scales up, the cost could rise.

At the moment, he says, India uses small rocket launchers because they don't have anything stronger. But that means India's spacecraft take much longer to reach their destination.

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So, when Chandrayaan-3 was launched, it orbited the Earth several times before it was sling-shot into the lunar orbit, where it went around the Moon a few times before landing. On the other hand, Russia’s Luna-25 escaped the Earth’s gravity quickly riding a powerful Soyuz rocket.

“We used Mother Earth's gravity to nudge us to the Moon. It took us weeks and a lot of resourceful planning. Isro has mastered this and done it successfully so many times.”

But, Mr Bagla says, India has announced plans to send a manned mission to the Moon by 2040 and it would need a more powerful rocket to fly the astronauts there quicker.

The government recently said 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 also cost more.

Also, Mr Bagla says, India is in the process of opening up the space sector to private players and it’s unlikely that costs will remain so low once that happens.

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