Anita Sengupta , Nasa scientist. Picture by Bishwarup Dutta
Rocket science and sports bikes! Shera Bangali Anita Sengupta was at home on both topics at a programme in the city on Friday.
The engineer at Nasa’s Jet Propulsion Laboratory spoke about the supersonic parachute as big as the Science City auditorium — the venue of her talk — that she had designed to put Curiosity on Mars.
Later, the daughter of a Bengali father and a British mother explained why she prefers a 600cc Yamaha to a car in LA traffic.
“Motorcycles are more fuel-efficient, cost less and you get through Los Angeles traffic faster because you can ride between cars just like in India. The traffic is not as bad in Los Angeles as it is here but it’s the same principle,” she said.
Before she walked on stage to deliver her lecture — Curiosity’s Entry Descent and Landing on Mars — acting US consul-general and the director of American Center, Jeffrey Reneau, introduced her as “Shera Bangali…who loves fast motorcycles and travelling. She rides a 600cc Yamaha through the busy streets of Los Angeles”. The packed auditorium applauded, while about 1,000 people watching the show on a screen outside went into raptures.
“The Mars atmosphere is so thin that you have to have a big parachute. The parachute will probably occupy this room. So imagine a parachute the size of this with the rover the size of a car landing on Mars,” she said.
The talk was organised by the Center of Excellence in Space Sciences India (CESSI)-IISER Calcutta in association with American Center, Pashchim Banga Vigyan Mancha and Science City.
Sengupta was a member of the team responsible for slowing down the spacecraft so that it landed softly on the Martian surface on August 6, 2012. “The rover was coming at 13,000 miles per hour… a traditional airplane flies at 500 miles per hour. (The rover’s speed had to be reduced) From 13,000 miles per hour to 2 miles per hour in less than seven minutes.”
The principle of aerodynamic drag was used to reduce the speed to 900mph, the supersonic parachute reduced it to 250mph and retrorockets cut it down to 2mph before the rover landed perfectly on the red planet.
“Perhaps one day human beings would want to colonise another world... Mars is a pretty good place we could colonise,” Sengupta said.
Since Mars’s gravity is one-third of our planet’s gravitational pull and its atmospheric pressure is just one per cent of what we have on Earth, she said the future colonisers would have to wear pressure suits and carry their own air and water supply.
“It’s feasible, something that will probably happen in future.”
On why Curiosity was landed on Gale Crater that holds an ancient water body, she explained with a question: Would an alien race looking for life go to the middle of the Sahara desert or try their luck in Calcutta? “You would probably go to Calcutta.”
What about biking on Mars? “That won’t be efficient use of oxygen… there are better ways of getting around.”
In Calcutta, she has given her Bengali palate a nice workout. “Everyone treated me wonderfully. The food is delicious.”
And she plans to pack some Anarkalis in her suitcase before she flies back to Los Angeles.