It is quite possible for someone to ask why, in the age of the Internet and the Television, and realtime weather reports, we need APT images. But, you will never know the joy of building your own equipment, and receiving your very own satellite images, until you have actually done it!
Simple visualizations (such as the one shown in the figure) of this curvature, typically appeal to a 2D fabric of space curved into a third dimension by the presence of a mass such as the earth. This curvature creates a three dimensional "well" into which other masses fall, thus resulting in what we perceive as gravity.
...here at last, we have these spectacular images - images that rained down from the sky! It's true that they are still imperfect, and rather noisy (a situation that I intend to fix soon). But, anyway, here they be recorded, before the miracle of the moment passes away...
Maxima is a computer algebra system. That's kinda like a calculator that can do algebra instead of just numerical calculations! I let Maxima cut through all the algebra of the RC phase shift network. Lo and behold, here we have the results, achieved almost painlessly!
I often hear all this talk about how the Explorer is a "low end budget device", about how 600 MHz is just too slow, and so on. But frankly, I can only classify all this as sales talk, or perhaps uninformed talk. Ice Cream Sandwich is not in any way slow on the Explorer, all hardware works fine, and I would certainly recommend anyone with an Explorer flashing to CyanogenMod 9.
...in effect, SSB radio is like shouting above the din of the noise existing in the band. The noise always exists in the band, and in order to be heard, one must shout above the noise.