There is just one cosmic occurrence that could create this apparently red ring of fire around Earth, as pictured below. The answer is simple: A total lunar eclipse as seen from moon. So what this red ring actually is and why it's vital. Thanks to this beautiful video by NASA's Scientific Visualization Studio, you can witness what a total lunar eclipse will appear as seen from moon.
If there were human camps on the moon, this would be their form of a total solar eclipse. The variance is just that as an alternative of the moon eclipsing the sun, it's the Earth eclipsing the sun.
