On November 5, 2013, a rocket launched toward Mars. It was India’s first interplanetary mission, Mangalyaan, and a terrific gamble. Only 40 percent of missions sent to Mars by major space organizations—NASA, Russia’s, Japan’s, or China’s—had ever been a success. No space organization had succeeded on its first attempt. What’s more, India’s space organization, ISRO, had very little funding: while NASA’s Mars probe, Maven, cost $651 million, the budget for this mission was $74 million. In comparison, the budget for the movie “The Martian” was $108 million. Oh, and ISRO sent off its rocket only 18 months since work on it began. A few months and several million kilometers later, the orbiter prepared to enter Mars’ gravity. This was a critical moment. If the orbiter entered Mars’ gravity at the wrong angle, off by so much as one degree, it would either crash onto the surface of Mars or fly right past it, lost in the emptiness of space.
Back on Earth, its team of scientists and engineers waited for a signal from the orbiter. Mission designer Ritu Karidhal had worked 48 hours straight, fueled by anticipation. As a child, Minal Rohit had watched space missions on TV. Now, Minal waited for news on the orbiter she and her colleague, Moumita Dutta, had helped engineer.
When the signal finally arrived, the mission control room broke into cheers. If you work in such a room, deputy operations director, Nandini Harinath, says, “you no longer need to watch a thriller movie to feel the thrill in life. You feel it in your day-to-day work.”
This was not the only success of the mission. An image of the scientists celebrating in the mission control room went viral. Girls in India and beyond gained new heroes: the kind that wear sarees and tie flowers in their hair, and send rockets into space.
The rocket is going to leave. It’s not going to wait for anyone.
When Moumita Dutta was in the ninth grade, she studied light and found it fascinating. That obsession led to her study of engineering. She was in the eastern city of Kolkata, India, in 2006, when she read in the newspaper that India was preparing to launch its first moon mission. It was a chance to make up for a national opportunity India had missed a half century earlier. ISRO had been established in the late ’60s, in the thick on the moon race. But as a space organization in a newly independent country with extremely limited resources, the agency never participated in it. India’s 2008 mission to the Moon was a long time in the making, as historic as it was groundbreaking. “I thought the people who worked on it were so fortunate.” Moumita left the offer of a PhD abroad and moved halfway across the country to join ISRO in its mission to the Moon.
When ISRO announced the Mars mission in 2012, its primary objective was to build a capability to enter Mars’ gravity, and once there, conduct scientific experiments. The mission, especially considering the country’s limited resources, would have to be completed in record time. The rocket had to be launched when the distance between Earth and Mars was shortest, in mid-2013: only 18 months to plan, build, and test everything onboard. The orbiter had to enter an elliptical orbit around Mars from behind the planet, cutting off all communication with Earth at the most crucial stage in the mission. That would require full autonomous capability to be developed to keep it functioning. The orbiter could carry 5 sensors to carry out scientific experiments. The caveat: they would have to weigh under 15 kilograms, or 33 pounds, put together.
Moumita knew sensors. Now, she was tasked with building and testing a first-of-its-kind scientific instrument to detect methane on Mars.
It turns out the sensor Moumita worked on couldn’t have been more timely. In 2014, NASA’s Mars rover, Curiosity, detected a spike in methane in its immediate surroundings. Since the presence of methane could indicate that either life or water were once present on Mars, it was an exciting discovery. But to draw meaningful conclusions requires a scientific instrument that can detect even the smallest amounts of methane on the entire surface of Mars, and do so over all seasons, for months and years. Searching through the collected data would be “like searching for god,” as Moumita puts it, “of course, god, in this case, is our scientific objective.”
The demanding sensitivity of that quest shaped the design of the ISRO Methane Sensor for Mars. Moumita had worked on 12–14 payloads prior to this mission, but this was a different beast. “We were building something that had never been built before, so everyday was a new challenge,” she says.
Moumita and her colleagues concluded that their best shot at recording those fine measurements lay in a choice of an optical filter that had never been flown in interplanetary missions: etalon. It was untested, but sensitive enough to detect the smallest amounts of methane and it would bring down the weight of the sensor to under 3kg or 6.5lb. Moumita conceptualized, developed, and executed tests for the etalon. It was so critical to nail this experiment, the chairman and directors of ISRO were present for the tests.
Under the eyes of her bosses, a nervous Moumita began the trial run. “I put the etalon in the test setup, so anxious to see whether it’d give me the performance we were looking for,” she says. Then she inserted a tiny methane cell between the etalon and the parallel beams of light in the setup. The signal from the etalon dropped. “When I saw this, I thought “whoa!” I became emotional. What we’d built could actually detect methane. We knew that this would work!”
The sensor would fly to Mars, and it would have Moumita’s touch. All that remained were months of 18-hour days to make sure the mission launched on its absurdly optimistic timelines. For Moumita, the time pressure was a non-issue.
“There are long hours,” she says. “but whenever I think that the sensor I am working on will benefit my countrymen, it feels worth it.”
“When fiction turns to reality, you won’t know.”
India is a country of contradictions. There is the India that grows its economy, then there is the India with extreme income inequality. One India shows its girls they can grow up to be rocket scientists, the other doesn’t ensure her that the rights to education and safety are a given. While one India follows the shortest trajectory to Mars, the other India remains inaccessible by road.
Growing up in the 80s in the small town of Rajkot, India, Minal Rohit watched the launch of a satellite on television. It was so exciting, she thought, “kaam karna hai toh aisa karna hai.”
If you have to work, do such work.
For mission-driven girls and women, the culture in India can sometimes be claustrophobic and a career can seem like an act of rebellion. Minal’s parents never let that culture pervade their home. When it was suggested that she not pursue further education—“How would she get a suitable match for marriage?”— her father had none of it. “My dad was adamant,” she says. He said, “she’ll find a match herself if she doesn’t get one, but my daughter will study.” Even so, engineering was an unusual career choice in Rajkot at the time, particularly for women, and Minal decided medicine might be more appropriate. Minal’s parents transferred her from a Gujarati- to English-medium school. When she didn’t clear medical entrance exams, they encouraged her to try her hand at engineering instead.
Of course, that was what she’d once daydreamed about as a child.
Minal started her career at ISRO providing medical and education access in rural India using the agency’s communication satellites, where such services are life-changing to thousands of people. She was fortunate to have the support of her parents, as well as her husband. But her drive was not sated. “Life is comfortable, so I have to find ways to break out of my comfort zone again and again in my work,”she says. Otherwise, “when fiction turns into reality, you won’t know.”
The Mars mission was as far out of a comfort zone as a mission can be.
The impossible timeline forced innovation. A regular mission is like a relay race. Subsystem teams, like Moumita’s optics team, build their devices and hand them over to the systems integration team. That group ensures that all subsystems—optics, electronics, mechanics—work harmoniously together and meet the performance criteria. Then, the system is passed on to be integrated on to a model of the orbiter, the qualification model, which undergoes strenuous testing. The orbiter that finally, finally flies is a replica of this model.
“Think of it like the elder son and the younger son,” says Minal. “The younger son gets all the attention whereas elder son has to undergo all the hardship. So if the elder son clears rigorous tests, it means the younger one will definitely clear too. Generally, only once the qualification model is finished will the flight model be thought about.”
But that was not the case with the Mars mission, which did not have the luxury of time to conduct a relay race. This more of a juggling act. “The qualification model and flight model were being built in parallel,” says Minal.
Her role was to help integrate the components of the methane sensor into a finely tuned scientific instrument. Normally all of her work would have been done in the qualification model, with a margin of error that could have been corrected in the final flight model. But since everything was overlapped to meet the deadline, that margin didn’t exist.
“In space, no mistake is acceptable,” she says. “We call it zero defect.” So when all instruments were coming in for testing on both qualification and flight models at the last stage, Minal recalls, “there was a lot of pressure. No mistake was acceptable, not in a single wire connection. I would say that even the patience I don’t keep with my own son was tested in this mission.”
Minal meticulously worked out the plans and procedures to integrate the subsystems of the methane sensor. Usually, when subsystems arrive at Minal’s desk to be integrated, they’ve been fully tested and certified by subsystem engineers. In this mission, Minal recounts, “they were still being tested by subsystem teams. So we had to trust orally, without documents or certificates, just from the engineer saying, ‘ok, I’ve tested it my way, now you take it.’ That’s all!” She adds, laughing, “I was praying to god that when I press the on button, it should switch on, and not blast something!”
There were no blasts. The orbiter could be readied for the one that counted: the blastoff into space.
“I would look at the darkness and wonder what lay beyond it.”
The average distance between Earth and Mars is 225 million kilometers. This means that a signal from the Mars orbiter takes 12 minutes to arrive at ground control. Twelve excruciating minutes before you potentially know something is wrong, and another 12 endless minutes before your command to correct it reaches the orbiter. If your orbiter is on the brink of disaster, that 24-minute turnaround will probably be fatal.
That’s why a Mars orbiter requires an ability to operate fully autonomously. With every space mission, ISRO’s team of scientists are building their capabilities. The 2007 mission to the Moon built their capability to leave Earth’s gravity. The Mars mission would have to add to that an autonomous software system, advanced enough to diagnose and self-correct any problem that outer space could come up with.
Mission designer Ritu Karidhal led the design and development of this system. “It is like the human brain. It receives signals from sensors like your eyes, ears, nerve endings. If there is a problem anywhere in your body, your brain reacts immediately. That is what we had to build for the orbiter in ten months from scratch. We had to take each element —sensors, activators, motors—and understand how it may behave or misbehave.”
When Ritu first became interested in space she didn’t quite realize it would be so technical. Then again, she was only three years old. “I used to ask why the moon was growing bigger and smaller. I would look at the darkness and wonder what lay beyond it,” Ritu recalls. “I thought space science was just about astronomy, watching stars. In reality, it’s very technical work.”
Nineteen years ago, Ritu left her hometown of Lucknow, India and moved across the country to become a scientist. “It wasn’t an easy decision to make but my parents always supported me,” she says.
On launch day in November 2013, those dreams met reality as Ritu stared at the monitors in the mission control room. Her autonomous system was destined for the ultimate test.
Also in the room was Nandini Harinath, deputy operations director for the mission.
There wasn’t one particular moment that triggered Nandini’s interest in science. “My mother was a maths teacher, my father is a great lover of physics. I think for me, science has just always been there,” Nandini says. Maths was such a frequent topic of conversation at home, Nandini reckons she had familiarized herself with it before she even learnt to speak. With her father, she remembers studying the constellations until she could recognize the different stars in Bangalore’s night sky. “Of course, I didn’t think I’d ever join ISRO, but 21 years ago, it just happened.”
For Mangalyaan, Nandini did the math to determine the trajectory that should take it to Mars.
During takeoffs, Nandini says, “I always have butterflies in my stomach.” Once the orbiter launched, the team had to perform critical operations to get it to leave Earth’s gravity for Mars. As Nandini describes them, they “were a one-time affair. You do it right, or you don’t.” The orbiter followed a predetermined slingshot-like path, revolving around Earth six to seven times, firing the engines with each revolution, until finally, it gained enough velocity to leave Earth’s sphere of influence at precisely the right angle toward the red planet. The first phase of the mission was over.
Nine months later, the orbiter would be ready to enter a new world: Mars.
In the interim, Nandini worked at mission control to make sure that the Mars probe followed the trajectory that she helped calculate and design. If the capsule veered from the planned trajectory at all, her team had the wherewithal to steer it right back. While Nandini was being tested on the Mars mission, her daughter was taking her final high school exams. Nandini would return from the mission control room at midnight, waking at 4 am to study together with her daughter.
But on September 24, 2014, there would be no opportunity for adjustments: it was time for Mangalyaan to fly itself, using the system that Ritu helped design. At 7 am that morning, the orbiter sent a signal confirming that the sequencer on the onboard autonomy system had started firing. It was ready to enter Mars’ gravity. The orbiter oriented itself using activators and wheels until it was at an insertion angle within a one degree margin of error.
Twenty-one minutes later, as planned, the engine started firing. Four minutes after that, the signal stopped. The orbiter had gone behind Mars. If it entered Mars’ gravity at the correct angle, it would send a signal back to Earth. If it didn’t, Mangalyaan would never be heard from again.
“Every minute,” Ritu recalls, “we were keeping track of data to try and calculate if an anomaly was occurring.” But of course there was no way to alter the mission itself. For the next 26 minutes, Ritu and Nandini’s teams waited in the complete silence of the mission control room.
Then, at 8 am, a signal arrived on Earth. And the world saw the celebration, not only of Indian science, but the amazing women at its center.
“Worldwide, half of all brains are in women.”
Astrophysicist Vera Rubin, who discovered dark matter, famously wrote that she had three basic assumptions concerning women in science:
"There is no problem in science that can be solved by a man that cannot be solved by a woman. Worldwide, half of all brains are in women. We all need permission to do science, but, for reasons that are deeply ingrained in history, this permission is more often given to men than to women."
Nandini sadly agrees that this is still the case for most women in her country. “Maybe it’s our culture,” she says. “It puts so much pressure on the woman that even if she’s ambitious and has the talent to go far, she cannot unless she has full support at home.”
Yet the women of ISRO may have an impact on that. These heroes credit their opportunities from permission and support, silent or otherwise, from their parents. The rolls of the Indian space agency indicate that others are following. Today, says Moumita, “The number of women in space science at ISRO has skyrocketed in the last few years. This shows that there is more support for women joining such work.”
Indeed, almost a quarter of ISRO’s technical staff today is women. There’s a long way to go but space missions are so tricky that all hands—all brains—must be on deck. If you’re reaching for the stars, you cannot build a glass ceiling between Earth and space.
That is what propels orbiters into space and scientists into the limelight. And then the cycle can continue—a relay race whose time has come—as girls see the sarees in mission control and realize that they can do this, too.
“If you have a true wish, you will get to it, either this way or that way,” says Minal Rohit, whose sensor continues to measure methane on Mars. “I always say, keep short term goals so you can find the motivation to meet them. Then, keep a bottom-line goal somewhere in your brain, a clear statement of what you want in life. One big dream, many small dreams.”
“Helping the common man is my big dream,” she says, “Mars was a small dream. Now I think: what next?”
The sky is not the limit.
