Not sure how many people picked up on this, but I only did today.
Studying numerous pics of Curiosity, I noticed the 'holes' in the tread of the wheels . I thought they might have something to do with traction/ dispersing dirt/ dispersing water ( hehehe). Then I noticed they were random holes at different lengths.
Google is my friend....
"Though its landing was entirely different, Curiosity learned some tricks from Spirit and Opportunity. Those rovers' wheels had small holes by which they were clamped to their landing pads before being released. Later, the rovers' handlers found they could see when the wheels were slipping on the sandy Martian surface by measuring the distance between the marks left by these holes in the rovers' tracks.
So Curiosity also has holes in its wheels, which spell out "JPL" (for NASA's Jet Propulsion Laboratory, where the rover was built and is operated) in Morse code."
from
this site.
and attached is a pic to clarify
Love that little touch of leaving a 'mark' on Mars
-.-. .... . . .-. ...
Bartman
