We start off with a ''sponge'' that at ground level absorbs the thicker ''water'' and emits ''water'' at an equal rate. When we move the ''sponge'' at ground level the ''sponge'' absorbs less, so emits less. When the ''sponge''travels further way from the ground, the ''water'' becomes less dense, and the ''sponge'' absorbs less and emits less. When the ''sponge'' approaches the sun, the ''water'' gets thicker again, and the sponge will absorb more ''water'' than it can emit , the ''sponge'' will be no more? added- I know how much most of you do not understand different content, so the ''sponge'' is obviously the Caesium atom. Would 9,192,631,770 hertz (Hz = cycles/second) be a steady state frequency? steady state noun an unvarying condition in a physical process At ground level does the field density vary any? or is the field a steady state density at ground level?