For the sketch on the left, I used #2 and #4 pencils on art paper, this was my warmup sketch. I used a grid to improve the sketch accuracy, you can see some artifacts of that on the sketch.
The right sketch was my second attempt 4 days later using black construction paper and kid's white chalk sharpened to a working point. I used a blending stump and a eraser shield on this one. My conclusion: white on black paper is a great media for the moon. I intend to use this technique during the next lunar month for some real-time effort on interesting objects.
NOTE: the image scan doesn't do justice to my originals, it is too coarse displayed in this format.