This new photo shows the scale of the massive Perseverance rover

You don't even have to be a science fan or spaceflight junkie to know about NASA's Mars rovers. It's big news when the space agency sends fancy new hardware to Mars, and you've no doubt heard the names Sojourner, Opportunity, Curiosity, and Perseverance many times by now. What you might not know is how the rovers have evolved over time, particularly with regards to their size. Without anything to provide a sense of scale in the Mars "selfies" that the rovers have sent back over the years it's ha...