17 January 2008

Jean Preston, Counsellor for Environment, Science and Technology, interviews Rick Grammier, January 17, 2008

Begin transcript

Hi, this is Jean Preston, I’m the Counselor for Environment, Science and Technology at the U.S. Embassy here in Rome and I have with me here Rick Grammier, of the U.S. International Aeronautics and Space Administration, NASA’s Jet Propulsion Laboratory, which is part of California Institute of Technology.

Rick is the Project Manager to the Juno mission an unmanned mission to Jupiter which is being planned by NASA to launch in 2011 and in which the Italian Space Agency (ASI), is an important partner.

Rick, I wonder if you could tell to me what are the management engineering challenges for implementing this type of mission to Jupiter?

Well. There are actually quite a few. Let’s see if we started with the management side of the house, this is a very large mission, first off, and we have major partners not only in building the spacecraft itself but also the various scientific instruments, so we have basically eight scientific instruments and they are being built all over the United States and in addition over here in Italy, as well. So you have to really manage those developments and schedules all together and on top of that we also have a major spacecraft system contractor Lockheed Martin which is doing a lot of the design for significant portion of the spacecraft itself. So really pulling all these together and having a management system in place to quickly identify problems, and take care of those, make sure you have excellent communications to start working on the design and resolve issues and you have the systems in place, automated IT systems to actually track all this and update rapidly and have communication without spending your entire life on an airplane it is quite challenging, it is a very large project.

I can imagine.

Now, from an engineering view point, there are so many things you could point to, but I guess the ones that I would point mostly to represent the challenge, is first of all the harsh environment that we are going have to operate in at Jupiter. It is a very harsh environment for many aspects, whether it’s the radiation belts themselves or the magnetic field lines you heard Scott talk about earlier, they are going there for the science and also has some issues that are produced on the spacecraft that we have to offset. And then of course we are also the first solar powered mission to go this far into deep space and designing and developing those solar rays to provide sufficient power at that large a distance when you’re only getting about 3% of the solar radiation that you get here at Earth is quite challenging.

I can imagine. What is new and different in particular about Juno compared to other inter-planetary missions?

Well, actually one of the newer things is kind of returning to an older thing is that we actually spin-stabilize spacecraft. I would say probably in the last decade and a half or two, most of the spacecraft had been three axes, what we call three axes stabilized. But this in fact is a spinner spacecraft that we have done because it simplifies the science and the actual type of orbit that we are doing at Jupiter itself. The other part of this as I mentioned before, is the solar power, we’ve had to actually do a lot of special testing and analysis of how solar cells perform in this high radiation environment, but at the same time at very low temperature and low incidence of the solar power there and based on those tests we have had to come up with what we think is the appropriate size and number of cells and therefore set the size of these very large solar panels that we have – they’re about seven and a half to eight meters long each and we are flying three of those. Last, but not least, because of the high radiation environment, we are having to shield our main avionics and electronics in a way that allows us to operate within that environment for at least a year and so we are the first spacecraft to really fly all that in what we call a radiation vault, so right in the center of the spacecraft we have this massive vault, that we have placed of most of our sensitive electronics inside of that and that is a really big challenge because you don’t necessarily have a lot of room, you can only…I mean these things are massive so you want minimize the amount of room, at the same time you get to have enough room to get all the equipment in, but you don’t know what size, final size the equipment’s gonna be, then you have to route all the cabling and then, last but not least, you have to be able to operate that at a temperature, keep the temperature controlled, so it doesn’t get too hot or too cold, so it’s quite an engineering challenge.

So we have a radiation vault with equipment from the US and Italy, hurtling through space for 6 years…to…

That’s five, that’s correct, it’s about five-year flight after launch, and then we…the basic mission is to last a year in orbit we basically go into eleven-day orbits and then do 32 of those orbits in order to collect the science that Scott (Bolton) wants so badly and it takes a while to do that and fill in all the gaps of knowledge plus have enough flexibility and if you have something go wrong during one of the orbits you can recover that science.

Rick, thank you very much for coming.

You are quite welcome. Thank you very much.