When Curiosity landed three weeks ago today, many news stories were quick to point out it is the biggest rover to date. They said it's car-sized. But what does that mean - are we talking a Hummer or a Mini? And how did its predecessors measure up? While snooping around NASA's Mars mission sites, I found these gems. Why they didn't get more traction in the media when Curiosity landed, I'll never know. But if it's our job here at Symbiartic to point out images in the service of science that excel for one reason or another, well, I'd be remiss if I didn't pull these out of the NASA archives to share with you.

Meet your Mars Rovers:

Now, astute readers will wonder how NASA took this photograph since the actual rovers are hundreds of miles apart on the Martian surface and were constructed over the course of a decade. Pictured here are the earth-bound, test-rover "cousins" of the true rovers: Sojourner (the shrimpy one, front and center), Spirit & Opportunity (mid-sized, respectable), and Curiosity (now, that's a rover!). But that is immaterial - what matters is that this image shows context and context draws people in. That's why I like the following image even better. The addition of people for scale is a simple trick, but it never gets old. In essence, you're relating the information in the photo back to the viewer. And let's face it - we never get old, do we!? (Insert New Yorker cartoon with caption, "Tell me more about me, dahlingk!")