As an Indian Institute of Technology, Kharagpur student, he always asked himself if life existed beyond earth. So it was a dream come true when he was selected for Mission Mars.
"I landed in USA as a 23-year-old graduate like any other boy from India," said 
(33), Planetary Geologist, National Aeronautics and Space Administration, in Mumbai. "So when I was selected for Mission Mars in 1993 I felt great. However, I didn't believe that I was the only Indian scientist working on Mission Mars until it was pointed out to me."
The National Geographic Channel had invited him to India to promote the Mars Exploration Rovers Mission.
He had worked on the first Mission Mars in 1993, which failed.
In 1997 he became the only Asian to serve on the Mars Pathfinder Mission Operations. As a member of that mission, he conducted chemical analyses of the rock and soil at the landing site.
In 2001 he was associated with the Mars Odyssey Orbiter; and now in 2004 he is working on MERM.
The MERM team, co-headed by Cornell Astronomy professor Steve Squyresm, laboured to prepare Spirit and Opportunity, the two golf-sized rovers, for the rigours of the voyage to mars.
Spirit landed on mars on January 4; Opportunity is scheduled to land on January 25.
National Geographic will air the programme Mars Mission on January 11, 2004, at 2000 IST.
On his role, Dr Ghosh said, "I was the first to analyse the rock on mars in 1997. As a geologist, I was the first person to announce the tentative result. We found something that was very unexpected, which was interesting. It was very different kind of rock."
Asked if he shouted 'Eureka!' he smiled and said: "No way. In science if you find something new you put a question and say, 'let me recheck'. You think you are making a mistake. I checked and rechecked. The other people then checked. But the first response is that this is not possible. This is how science progress."
Asked if he believed there was life on mars, he said, "It is too early to say This may be true or may not be true. It cannot be a straight answer. There are too many similarities between earth and mars. There are storms, volcanoes and dunes on mars just like on earth. So we don't know whether there is a possibility of life."
He added: "There are pictures of bacteria kind of material to be found on mars, but there are only debates on whether those pictures are truly of bacteria or not. We might be able to know the complete truth only if we send a human being to mars or we get more details from our latest Mission Mars."
However, Dr Ghosh pointed out that to send human beings on mars was a gigantic task. "It takes six months to reach mars as it is millions of miles away. And to reach mars and do research you need water supply for human beings for at least 18 months. So the task of sending human beings is huge now."
About his latest assignment, Dr Ghosh said, "In this mission I am working on atmospheric science and geology part. I am in India only to explain our first mission of NASA's Rovers spirit that landed on the surface of mars on January 4. Now our second mission is called as Opportunity that will accomplished on January 25, 2004."
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