Neat infographic and how do you make lines like this?

Question

Here is the infographic:
http://www.stevey.com/wp-content/uploads/2009/01/50-years-exploration-huge.jpg
I can't figure out if these lines rendered by hand or done with some application -- anybody suggest an approach?

Answer 1

I can't figure out if these lines rendered by hand or done with some application
Probably both.
You utilize whatever geometric automation is made available in the feature set of the drawing program you are using, and complete the rest with other features and/or manual path-specific manipulations.
In general-purpose drawing programs like Illustrator, you could, for example, use features like Offset Path or the Polar Grid tool to draw the concentric ring portions of the paths, and use Blends or the Reshape Tool to draw the converging portions of the paths.
If drawn in Corel Draw, for example, its Contour Tool might have been used for the concentric portions.
Often, several different approaches can accomplish the final art (some more efficient than others).
The general process is:
Study the geometry needed for aspects that suggest they might be automated or at least semi-automated.
Determine which aspects need to be numerically accurate (as opposed to merely aesthetically pleasing).
Consider the automated features of the program you are using (requires, of course, proficiency in the program.)
Based on that knowledge (of the requirements and the capabilities of the program), devise a procedure that meets the requirements, adding manual path drawing where you have to.
On the other hand, it's entirely possible that the orbits are drawn entirely automatically by a program that interprets numerical data as curves. For example, a CAE program might have modeled the paths from numerical data and exported them as 2D paths that were then imported into an ordinary drawing program for artistic treatment and embellishment (in much the same way you might take a mathematically-correct 2D perspective drawing exported from a modeling program and then "make it pretty" it in a drawing program).
Some ordinary drawing programs (Canvas, for example) include features that can plot curves from algebraic curve functions. Some ordinary drawing programs (Illustrator, Corel Draw, Canvas) can be scripted to draw paths from numerical data (although unlikely for the whole paths shown in your example, since the geometry would have to be tediously converted to control coordinates for Bezier curves).
So there are several ways to skin the cat; but you first have to know which cat has to be skinned (i.e.; what the real requirements are). Are the orbits actually accurate flight paths, or are they just "artist conception" interpretations? That's not clear from just looking at your example.
JET