(Image courtesy: Pallava Bagla)

Dr. Stewart Nozette from the Lunar and Planetary Institute, Houston explains how NASA's instrument MiniSar or the Miniature Synthetic Aperture Radar being flown atop Chandrayaan-1 will be the most extensive search for water ever on the lunar poles which, if found, will make it easier for humans to colonize the moon.

Pallava Bagla: So Minisar is going to be the first very extensive search for water on the moon?
Stewart Nozette: Right. First very extensive search from orbit.

Pallava Bagla: From orbit.
Stewart Nozette: Right.

Pallava Bagla: And what happens if we find water?
Stewart Nozette: It really enables people to be able to live for long periods.

Pallava Bagla: So it's going to be a forerunner for ultimate colonies to be set up on the moon?
Stewart Nozette: Right. If it's there. We already know water is essential for life.

Pallava Bagla: 70 per cent of me is water. Maybe more, because I am a fat man. But without that you don't have life
Stewart Nozette: Right. It'll be much too expensive to haul it off the ground.

Pallava Bagla: And to take it to the international space station, what happens?
Stewart Nozette:Well that's one of the things that is costly. Tremendous amount of their logistic support at the space station is just about water.

Pallava Bagla: And this Minisar, what does it do? It sends a beam down to the
Stewart Nozette: It sends a radio signal, actually it is basically very similar to a mobile phone or a wi-fi signal, that basically bounces off the moon's surface and actually goes below the surface of meter or two and if water ice is available, present, it gives a stronger, a different kind of reflection.

Pallava Bagla: So this instrument will work only at the poles, not on other places?
Stewart Nozette: It could operate anywhere on the moon but initially we are operating it only at the poles.

Pallava Bagla: So on the poles is where you expect water?
Stewart Nozette:Right.

Pallava Bagla: And we haven't found water ever on the moon?
Stewart Nozette: We've taken their help in previous measurements that suggest it could be there but it is not definitive. We needed to get more information.

Pallava Bagla: And how much are you paying ISRO to carry your instrument?
Stewart Nozette:Oh ISRO is, we are guests. We are not paying ISRO anything. It's a collaboration between ISRO and NASA.

Pallava Bagla: Oh it's a collaboration between ISRO and NASA where ISRO is giving you a free ride to the moon?
Stewart Nozette: Well, effectively.

Pallava Bagla: Effectively. And you are sharing data or something with ISRO?
Stewart Nozette: We're sharing all the data with ISRO.

Pallava Bagla: So when water is found and if there is spoils to be shared, ISRO and NASA and LPI would be together in that?
Stewart Nozette: We are all partners.

Pallava Bagla: We are all partners in that. And how much did it cost to put this Minisar together?
Stewart Nozette: It was tens of millions of dollars.

Pallava Bagla: That's expensive!
Stewart Nozette: But compared to a dedicated satellite it's pretty good deal for NASA.

Pallava Bagla: Oh so you get to fly your instrument without having to pay this hundred million dollars which ISRO is spending for this satellite?
Stewart Nozette: More in the United States, I'll say.

Pallava Bagla: So it's a good deal?
SN: Very good deal for NASA and ISRO. Really opens up collaboration between NASA and ISRO which hasn't happened on this scale before. So it helps us in a lot of ways.

Pallava Bagla: So did you enjoy working with ISRO?
Stewart Nozette:Yes, very much.

Pallava Bagla: Any challenges you faced?
Stewart Nozette: Distance, culture

Pallava Bagla: Distance meaning what, distance to moon and ISRO?
Stewart Nozette: This is between United States and India.

Pallava Bagla: Oh, okay, so the time difference and the air miles...
Stewart Nozette: A challenge of learning how to work with a new group a long way from home.

Pallava Bagla: And how confident are you that Chandrayaan will really reach the moon?
Stewart Nozette: Well, I am putting my faith in ISRO's gentlemen. If you are ready to go, then you are ready to go.

Pallava Bagla: And suppose it fails, is ISRO willing to pay back for the instrument? What happens? What's the deal?
Stewart Nozette: I think we are all kind of taking the risk together.

Pallava Bagla: Oh, so it's a fairly expensive risk you are taking?
Stewart Nozette: Well yeah, but we have another .NASA's also flying a satellite to the moon in the next few months. It has another version of the Minisar on it. So we'll sort of have a redundancy. One of the two will hopefully get to the moon.

Pallava Bagla: And get water.
Stewart Nozette: Right.