KARACHI: “Exploration is first about following the water. If there is water somewhere, it means that there is life there,” said Engineer Zainab Nagin Cox associated with the Mars Curiosity Rover project of the National Aeronautics and Space Administration (Nasa) during her presentation at the Rangoonwala Community Centre on Tuesday.

The event, organised by the US consulate, was attended by Suparco officials and students of space and planetary astrophysics.

Taking her audience on virtual exploration trips to Mars, the engineer spoke about the first Viking mission to the planet in 1976. The first successful landing on July 20 that year and the ones that followed provided the Nasa scientists and engineers an idea of the climate on Mars and Viking 1 and its sister craft Viking 2 beamed pictures, information, etc, back to Earth for six years.

But they were just fixed at one spot where they had landed. The Sojourner rover part of Nasa’s Mars Pathfinder mission in 1997 changed that. The spacecraft also helped the space administration test its airbag landing system. But Nasa’s next two missions to Mars failed.

“The next window to send a mission to Mars was coming up in 2003 when the planet was closest to Earth in 60,000 years,” said Ms Cox while adding that several other countries, too, had started sending missions to the red planet.

“But after two failed missions Nasa’s engineers were thinking of going back to the old things which had worked for them. It was decided to send rovers that were also robot geologists with cameras, X-ray machines, labs, etc, to the planet to find out if there was ever water on Mars in the past.

“With this decided, the engineers went to the scientists to know where they’d like the rovers to land. But the locations they pointed to, the engineers had a problem with as they thought those places would not suit the rover to move about freely. And what locations the engineers found favourable, the scientists thought boring. We had to find where the engineers could safely land the rovers and which the scientists also agreed to,” she said.

“That’s how the two rovers Spirit and Opportunity landed on Mars inside airbags,” Cox said while describing the six minutes of terror landing on Mars when everyone in the Nasa control room was holding his or her breath hoping for a safe landing.

“At the time, another two out of the three missions sent to Mars by other countries including Britain had failed. And here we were waiting for a signal from our rovers. There was nothing for 10 minutes, there was nothing for 15. But after 17 minutes, when everyone in the control room from all the countries also involved in the manufacturing of the rovers had almost given up hope, there was a signal. It did not feel like a robotic mission, we were all watching it on screen and it felt like we were on Mars,” she said. “And the servers went down because the world was watching, too,” she laughed at the memory.

Both the rovers, Spirit and Opportunity, found that there was once water on Mars. “But for how long it was there? Was it there long enough to create an environment for life?” She explained the next questions on scientists’ minds.

The next rover built for further exploration was the size of a car and engineers faced a dilemma about how to land something that big on Mars. “There were different teams working on its landing, how to steer it in the atmosphere, cruise trajectory, etc. Meanwhile, a sixth grader Clara Ma won an essay competition to name the rover. She named it ‘Curiosity’. That’s how she, too, became a full-fledged member of the team,” said Cox.

“With everything good to go, the engineers went to the scientists to ask them where they’d like Curiosity to land on Mars. The scientists since the first Viking mission in 1976 had been wanting to explore the Gale Crater, which has a mountain taller than Mount Everest right in the centre, and this time we could land the rover there,” she informed the audience, going on to report how Curiosity safely touched down on Mars on Aug 5, 2012.

“Like any tourist, first it took a ‘selfie’, then looked at its feet as it had literally fallen from the sky before going about its work,” she said. But the engineers and scientists’ work wasn’t done with just the safe landing. “When the rover goes to sleep we work on what she is to do the next day. It has already found out that there used to be a lake in the area it has been exploring. And not only had the water been there, it was right for human consumption, too. Mars was once habitable,” the Nasa engineer concluded.

Published in Dawn, May 28th, 2014