For Earth Day, one of NASA’s famous photos of our planet, take by a robot lunar orbiter in 2015.
Copyright presumably NASA. You can download a 12 MB high-resolution version from here.
One of Elon Musk’s odd hobbies is promoting the colonisation of Mars, as a failsafe in case humanity kills itself off on the one planet we know is hospitable to us. If we are really stupid and evil enough to do this, do we deserve to survive as a species? In any case, it looks if dealing with the greatest risk of species suicide, uncontrolled climate change, may well be cheaper to fix (here, here) than setting up a self-sustaining colony on Mars. Since one plan would save billions of lives and the other hundreds, it doesn’t seem a close call.