One is the visible spectrum, as mentioned above, and the other is the radio spectrum. However, not all of the radio spectrum is useable for space communication. The available window spans from about 30 MHz to 30 GHz, although these are not absolute end frequencies.
Isaiah 43:2 (BBE) When you go through the waters, I will be with you; and through the rivers, they will not go over you: when you go through the fire, you will not be burned; and the flame will have no power over you.saiah 43:2 (CJB) When you pass through water, I will be with you; when you pass through rivers, they will not overwhelm you; when you walk through fire, you will not be scorched-the flame will not burn you.
If I die young, bury me in satin. Lay me down on a bed of roses. Sink me in the river at dawn. Send me away with the words of a love song. Lord make me a rainbow, I'll shine down on my mother. She'll know I'm safe with you when she stands under my colors. Oh, and life ain't always what you think it ought to be, no.