Antarctic expeditions sail October through March, and levels of adventure and comfort vary, as do itineraries and pricing. Here are a few options:

AdventureSmith Explorations: Programs engage passengers in gathering data for oceanography, ornithology and glaciology during 12- to 15-day voyages; ships carry 112 to 114 passengers (adventure­smithexplorations.com).

Holland America: This company’s Zaandam (1,432 passengers) cruises past two or three days of Antarctic awe before returning to South America exploration; ships with more than 500 passengers are not allowed to land passengers (hollandamerica.com).

National Geographic: Trips include a 24-day journey with experts who add scientific, historic and biological expertise on a 148-passenger ship (nationalgeographic.com/expeditions).

Oceanwide Expeditions: Voyages to the Antarctic Peninsula include adventurous activities such as hiking, mountaineering and camping. Ships carry 116-passengers. Some cruises attempt to reach Snow Hill Island’s emperor penguin colony (oceanwideexpeditions.com).

Poseidon Expeditions: Among its offerings is a 15-day sail attempting to reach 66 degrees south — below the Antarctic Circle — with kayaking and camping as weather and ice allow. Ships carry between 100 and 124 passengers (poseidonexpeditions.com).

Quark Expeditions: This cruise line offers a range of Antarctic sailings in ships that carry from 110 to 199 passengers to the South Shetland Islands and the Antarctic Peninsula. Some emphasize adventure, and offer camping, snowshoeing, kayaking and more, while others focus on environmental learning or visits to emperor penguins (quarkexpeditions.com).

Silversea: This luxury cruise line offers 34 Antarctic sails from November through March (silversea.com).