Get image from internet and save to file using VB

Using the [login to view URL] site, post a link with appropriate variables and get propagation prediction image from voacap and store to an image file. The posted link is [login to view URL] where the upper case words are replaced with the proper values. The site in operation can be seen at [login to view URL] The resulting page comes up with a world map showing the predicted propagation for the information post. I want that image (and only the image) saved to a file. File name is not important at this time, but will eventually be voaYYMMDDhhmm.. A typical image (screen capture) is attache. Program is to be written in visual basic compatible with VS 2010 and be functions easy to incorporate into another project. Standard VS 2010 libraries will be use and no additional dll unless the dll is normally part of windows XP, 7 and 8.