Waypoint in space game

Hi. I'm making a space game and i have a question. I want to add system, where player can choose his planet or asteroid and waypoint system will appear on center of planet with icon and text displaying distance to planet. I already made that using text mesh, but if i am really close to the planet text quality is very bad and also I want to get always the same icon and text size all the time, whenever player is far away or close (text must face player). How to do this?

Also I want the text and icon disappear if I turn my back to the planet. (I don't know is this right, sorry for my english)