Comment by DavidSJ
7 years ago
Thanks for the answer! Apologies if this question betrays my ignorance further, but what would happen if a signal were reflected twice? Would the polarity flip back?
7 years ago
Thanks for the answer! Apologies if this question betrays my ignorance further, but what would happen if a signal were reflected twice? Would the polarity flip back?
Yeah, or if it reflected off an interface going from high refraction index to low (e.g. reflecting off an under-ice cavern or something). These are possibilities, but 1) the reflection is far away, so for this to be coherent, it probably must be some massive feature, and 2) ANITA also had a trailing balloon with a calibration pulser from which we could observe both direct and reflected pulses, and from that pulser, we never saw evidence of the reflected pulses not being flipped in polarity. Of course, that did not probe every region of ice and all incident angles, but it seems like if such a strange reflection were likely, we likely would have seen it there.
Nonetheless, we are working on simulating reflections off various ice models to see if we can come up with a plausible optics explanation (like pathological sastrugi).
> pathological sastrugi
I think someone just named the next big Ice band.
edit: Folks who work in Antarctica often refer to it as "The Ice".