Website logo animation, moving, expanding light

Hello, I don’t know flash quite yet, but for some reason I get asked to do flash miracles, so I think I will need some help on this one.
Here’s the basic idea:
I have this logo

and they want just something moving on it. So I decided to make a sliding, growing flash of light slide from the right of the underline to the left then fade out.
So I need advice for what to do. My brother has dabbled in flash and says that, using key frames, I could do something like have the light be a layer that I manipulate over a certain amount of frames. His other option was to make individual frames and just use flash as a frame organizer or gif animator. Ideas? Here’s the beginning an end images I was sort of thinking of:

to

but maybe brighter, i don’t know.
Thank you so much