The night side of Venus can be observed to glow thermally in a window in which the venusian atmosphere is transparent around 1000nm. It is necessary to greatly over-expose the bright crescent to show this, as I have done here. Some small contrasts can be seen on the night side and comparison with the relief map suggests the darker areas may correspond to the depressed areas of Sedna Planitia and Guinevere Planitia (purple areas in the relief map).