triple point

"Mars once was wet and fertile. It's now bone dry. Something bad happened on Mars. I want to know what happened on Mars so that we may prevent it from happening here on Earth." -Neil deGrasse Tyson Oh, it's true alright, something bad did once happen on Mars. And although there isn't any real danger of that happening to Earth, a little conversation I had earlier this week made me think that it's time to tell all of you a story about our red neighbor, and why it is the way it is today. You see, when we think about Mars, we think about the smallish, red, desolate world that fascinates us today…
People love to speculate that Mars was once a great place for life to form, and claim that there is plenty of evidence that there used to be oceans and rivers there. But this isn't true. People used to claim there were big Canal-like features on Mars, and used this as evidence that Mars was very wet. It was later realized that these weren't canals, but rather geological features caused by impact craters from astroids. But more recently, people have been claiming that images like the one above are examples of dried-up riverbeds. But this turns out not to be the case. When we take a closer…