"These are the first high-definition images taken of the sun going down and then going into darkness at the horizon [on the moon]," Joel Kearns, deputy associate administrator for exploration at ...

This puts the sun safely out of view, below the horizon. The relatively high angle ... can almost seem to extend all the way around the edge of the nighttime side of the planet now facing Earthward.

But the eastern edge of the moon’s ... band of sunlight over the lunar horizon resembling a diamond ring. Given the positions of Earth, the moon, and the Sun, the image recalls the many ...