Can any body tell me the official name of the color? I want to say light blue, but people may not be able to get the closest image in mind.
That colour is called cyan. ("Pure" cyan is often considered to be RGB 0,255,255, particularly in the context of computers or printing, but the term can refer to any colour between blue and green.)
This colour (or range of colours) is also often known by the names aquamarine and blue-green.