I need multiple text book illustrations made. They are technical as they are representing the orbital movement of the Moon, so a sense of geometry and perspective are important- in the attached image, the dotted line is the earth's orbit around the Sun, and the wavy line represents the Moon's slight upward and downward orbit as it circles the earth (from a side view). 14.7655 days correlates to degrees of the circle of the dotted line. Other images are similar. I made a project page to show the style I am looking for: http://shrifreedom.org/project-page/ Please give a link to similar portfolio work when replying for this job. I prefer to pay per image for the right artist.