Antarctica is one of the rare places on Earth that does not have an Indigenous population so every person that lives in or visits Antarctica is an alien!
Each summer about 500 people travel south, by ship or plane, as part of the Australian Antarctic Program. During winter the total Australian station population in Antarctica and on Macquarie Island, is only about 80 people.
Across the whole of Antarctica there are only a few thousand people living on the continent during the peak summer period. The most populous Antarctic centre is McMurdo Base on Ross Island, south of New Zealand, operated by the United States.