Sunset on Day 2 of my cruise to Antarctica. At 59°57'50" S 66°51'28" W, this photo was taken a bit north of what the Antarctic Treaty System defines as Antarctica. Namely, everything south of 60°S latitude.
Going to the extreme ends of the Earth, you start to approach the midnight sun. While the sun does set more or less, it seems to just sort of dip and come back, and not get fully dark. This photo was taken after 11pm and as you can see, it's still fairly twilighty out.
Stern deck of the Akademik Ioffe while cruising through the Drake Passage.