1 create sphere
2 create plane
3 create material matte shadow, then assign to plane
3 choose another material sphere for sphere geometry , change it's diffuse color to blue, set the Reflection of Maps to fall off
4 in the attribute panel of fall off change the white color below black from None to Raytrace
5 back to fall off material, in the Mix Curve panel, right click the top point then choose Bezier-Corner and drag the handle down
6 create a skylight in scene, open Render setup panel in Advanced lighting choose Light Tracer(make the Rays/Sample to higher value to get a better result)
7 Change background color from black to light yellow at environment and effect then render
