What Causes the Zodiacal Light?

In the early days of radio astronomy, astronomers wanted channel 37 to be clear so they could look for aliens and other radio sources in the sky. Another strange thing in the sky that people have seen is known as the false dawn. It looks like a shaft of light coming up over the horizon, even though the rest of the sky is black and filled with stars. Now it can be seen from multiple places in the solar system.