earthshine

Earthshine is also called “the old moon in the new moon’s arms”—a lovely turn of phrase that not nearly enough astronomers use.

The answer’s in the name of this phenomenon: earthshine.

Some of that sunlight travels through Earth’s atmosphere before it travels to the moon, and this can affect earthshine’s brightness, especially if the daylit part of our planet is strewn with highly reflective clouds.

Scientists found that nearly half these permanently shadowed polar craters are occasionally bathed in earthshine and have pinpointed the times when it would be easier to directly explore them in search of promising deposits.

Earthshine is a wonderful and beautiful thing to see, but we can use our equally wonderful brains to use it, like so many other natural phenomena, to learn more about the universe around us.