Ellipse with OuterGlowBitmapEffect
<Window x:Class="WpfApplication1.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="WPF" Height="230" Width="500"> <Canvas Margin="10"> <Ellipse Canvas.Right="20" Canvas.Top="5" Height="150" Width="150" Stroke="Black" StrokeThickness="1"> <Ellipse.BitmapEffect> <OuterGlowBitmapEffect GlowColor="Black" GlowSize="80" /> </Ellipse.BitmapEffect> </Ellipse> </Canvas> </Window>