Tonight a Crescent Moon Slips Below Venus, With Earthshine at Its Best
Between 21:10 and 21:55, low in the west-south-west, a crescent lit to 11.9 % passes within seven degrees of Venus. It is also the best evening this month to see the dark limb of the Moon lit by the Earth. Here are the two quarter-hours that matter, and the arithmetic of what is doing the lighting.