There is a diy option to totally control that light automatically and have it cycle through a normal day/night cycle. Its on another forum
Guide: Arduino based LED controller for Current Satellite LED+ I haven't tried it yet but plan to. It is a standalone thing also, no modifications to the ficture needed. Also if you wait a few months Current USA is making a timer for it that is supposed to do the same thing. It will most likely cost more but will be directly from the manufacturer. They recently released a timer but it does not control the moonlight features. The pro version that they are working on is said to control that though. The last couple of pages on the following post talk about the timer a little bit with some information from current usa.
Current USA PRODUCT LAUNCH
If cheap is important then the diy route would probably be cheaper and they guys who developed it seem to be freindly and helpful from reading through the thread