There are other applications. Let’s say you have a hypersonic vehicle, like a spacecraft that’s re-entering. You have this RF (radio frequency) blackout period because you have plasma that’s building up because the thing is getting so hot. There are a lot of charges floating around and when you try to transmit radio radiation, it doesn’t make it out because that plasma acts almost like a conducting box. That’s the RF blackout period. When the Space shuttle lands, there’s a blackout period when you can’t talk to them. Well, if you go to high enough x-ray energy you can beat that blackout period; you can beat the plasma and potentially communicate during the blackout period, or at least pieces of it. You’d want to do this at low data rate, but usually in that situation you just want to do housekeeping-type communications. So there is also that possible application, just because of the high energy, and there are other applications, as you might imagine.
NTB: Any commercial applications?
Dr. Gendreau: Well, for example, hypersonic vehicles. If there was hypersonic transport between here and Tokyo - I’m not sure about the blackout period there - there’s a potential that you could do a com link with a hypersonic vehicle that you couldn’t do with radio. That’s sort of speculative, but it’s possible.
NTB: What about the Black Hole Imager? What’s the current status of that project and will you continue to be involved with it?
Dr. Gendreau: That’s a thing that’s way out in the future - 30 or 40 years away. So we’re going to continue to get the technology going along for it. Using X-com as motivation for developing some of the key technology, i.e. pointing an optic very precisely, making the optics big and cheap and diffraction-limited, and putting all the infrastructure in place for making that thing happen, you basically have a lot of the key components for a Black Hole Imager in the future.
One reason for pushing for x-ray communication is a way to fund the technology development, which is kind of disappearing from NASA science right now. It’s a way to naturally connect with the vision for space exploration, thinking about ways to do communications over long distances.