(Image courtesy: Pallava Bagla)

Dr. Stas Barabash from the Swedish Institute of Space Physics is flying an instrument which is called SARA whose objective is to study how the environment interacts with the moon.

He says, space is not empty but filled with different kind of particles and these particles interact with the lunar surface.

Pallava Bagla: So Stas, what are you flying on Chandrayaan and has it been an exciting mission?
Stas Barabash: Well, for us, Chandrayaan is really exciting and it is our first joint mission with India and we are flying an instrument purely international

Pallava Bagla: Where, can we see the instrument on this model somewhere?
Stas Barabash: Yes, yes. SARA consists of basically three units, 1,2 and 3.

Pallava Bagla: So this is what is on the Chandrayaan?
Stas Barabash: Yes.

Pallava Bagla: Very close to the MIP instrument which India is very proud of..
Stas Barabash:Yes.

Pallava Bagla: So what are you going to be doing with this?
Stas Barabash: Well, maybe some background. Space is not empty but filled with particles. And these particles interact with the moon's surface and modify it. And that is what we want to study with SARA.

Pallava Bagla: But look, people think it's a vacuum there.
Stas Barabash: No.

Pallava Bagla: It's not a vacuum?
Stas Barabash: It's not a vacuum at all. Basically the sun is illuminating, the sun has been sending into space a lot of particles and these particles we call solar wind, and these particles can reach moon and they can interact as I said, interact with the surface and affect it.

Pallava Bagla: So what are you expecting? When Chandrayaan is there in orbit and studies, what are you expecting out of your instrument? What is the new science we can expect?
Stas Barabash: Well new science- as I said, first of all people know very little about how solar winds, that is type of particles which fill space, how solar winds interact with the surface. And it, particles impact surface and it releases surface materials in space and we wanted to understand how this process works and also we wanted to see what kind of particles are released into space.

Pallava Bagla: Solar wind also brings down helium-3. Is that right?
Stas Barabash:Yes, exactly.

Pallava Bagla: And are you looking for helium-3?
Stas Barabash: No, no.

Pallava Bagla: You are not.
Stas Barabash: Unfortunately not. But definitely would, since we won't understand how the solar wind particles are actually delivered to the surface, definitely our studies will .

Pallava Bagla:But there are other instruments which are looking for helium-3 on Chandrayaan...Moon Mineralogy Mapper probably
Stas Barabash:Yes, some instruments may contribute to this issue too, not only SARA, that is right.

Pallava Bagla: And how has your interaction been with ISRO?
Stas Barabash: Well it was really, it was really an interesting experience because of course there are differences in cultures, but that makes, when two are different I would say, we can take an example, when two different people come together they create some sense of completing you. It is not just a sum of two, it is more than that. That is how our cooperation between us and ISRO looks and each part brings something more and it's a real motive for the whole cooperation

Pallava Bagla: So did you learn something from ISRO?
Stas Barabash: Oh yeah, absolutely.

Pallava Bagla: What?
Stas Barabash: Well, to make also sure that things might be done differently in space business and that another way also leads to great success.

Pallava Bagla: So you think Chandrayaan is leading to collaboration and cooperation in international lunar missions?
Stas Barabash:Yes, I am pretty sure of that, and that much more cooperation will follow and for myself and my institute I can always say that we are really looking forward to see more opportunities because it was an exciting mission and we really want to continue.

Pallava Bagla: So you have been happy with the cooperation so far?
Stas Barabash: Absolutely.

Pallava Bagla: Any regrets?
Stas Barabash: No, no. What I would like to say is that particularly in SARA's case we have even more close cooperation with our Indian colleagues

Pallava Bagla: Who are you working with in India? Who is the person you are collaborating with in India on SARA?
Stas Barabash:Well we have very close cooperation with Space Physics Laboratory from Trivandrum and Anil is our main partner

Pallava Bagla: Anil Bharadwaj..
Stas Barabash: Yes, Anil Bharadwaj, and so he is SARA Indian PI.

Pallava Bagla: Okay, so SARA is being flown on an Indian aircraft but you have a joint PI. An Indian and a Swedish PI. That's right?
Stas Barabash:That's right.

Pallava Bagla: Oh, so it is even more intense
Stas Barabash: Exactly, so that is the point which I tried to make that in SARA's case some part of the instrument was built in Sweden, but our colleagues from SPL delivered the extremely important part of the instrument which is called digital processing unit, basically computer, which serves our experiment and which communicates with the computer on the spacecraft.