Please [help] me in creating a rising sun....

Here's a quick tip: Try to be a wee bit more specific when asking questions so that those of us who answer them can address the problem with a quick and accurate answer. You see, there are several ways to do a rising sun. You could do it with an animated texture, a background image for your camera that has the values for the sun keyed, a giant sphere that incompasses (sp?) your entire scene that has an entire sky mapped to it with a sun that can be rotated, an actual sphere for a sun with a texture that looks like a sun mapped to it, etc. You can additionally animate objects through motion paths, expressions, animated textures, and keys. Which one do you want?

Anyway, just trying to say that if you take the time to explain well, Simply Maya will give you an answer that much quicker! Also, I have a hunch that you're a bit new at Maya. You should seriously check out the FREE tutorials here. They are very helpfull and will get you on your feet in no time! Have fun.