><i>You'd think it wouldn't be a problem for all the technology available.</i><p>All the technology in the world can't trump the Laws of Physics. *Sigh* I guess it's time to do a little education.<p>><i>Why is the quality so bad, why not have colour, or more clarity like on spy satellites.</i>First thing, Saturn is <b>very</b> far away - anything from 1.1 to 1.6 <u>billion</u> miles away. Spy satellites orbit the Earth at altitudes anywhere from 300 to 10,000 km. Why is this important? Because signal strength falls off as the <b>square</b> of the distance. That means that a signal sent from Saturn would be 1/12,000,000,000th the strength of the same signal sent from Earth orbit.<p>So, what does that have to do with the price of tea in China? Not much, but it does affect the ability to send data from Saturn to Earth.<p>The effect is most famously stated as Shannon's Law (C = W log2(1 + S /N )) the important terms here are S (signal) and N (noise). If the signal is reduced by a factor of 1.2e11, then the channel capacity is accordingly reduced as well. (In actual practice, the DSN receivers are much more sensitive (increasing S somewhat) and the receiving dishes are much bigger (reducing N a bit) - but the theory is still sound.)<p>I'll finish this a little later (I just realised I have 10 minutes to shower, dress and be out the house), or anyone else is free to chime in. <img src="/images/icons/wink.gif" /></p></p></p></p></p>