Earth (1980)

A central premise of each of the incarnations of Battlestar Galactica has been the quest of the Colonial survivors for the planet Earth.

The arrival of the Colonials at Earth, however, has only been depicted in one series, as of 2007.

Dr. Zee's simulation of a Cylon Attack on Los Angeles.

In Galactica 1980, the Earth was discovered, but, much to the dismay of Adama and the survivors, the humans on Earth were underdeveloped and would not be able to defend themselves from the Cylons. The short-lived series primarily depicted the central character's adventures on Earth's surface, including its past through a means of time-travel.

Settings on Earth

Most of the Earth scenes in Galactica 1980 took place in Southern California, with the main exception being the time travel sequence to Nazi Germany (which still looked a lot like Southern California!) and the trip Troy and Dillon took to New York City.

Galactica 1980 Earth vs. 'Real' Earth

There are several places where the Earth depicted in Galactica 1980 was dissimilar to the Earth as we know it.

UBC News - There was no such news organization in Los Angeles at the time denoted.

Project Blue Book - Project Blue Book, a program of the United States Air Force to investigate UFOs, had long concluded by 1980. In the Galactica 1980 universe, a very similar program is very much still active.

Notes

There were hints in the Original Series that the Earth may be technologically advanced. However, perhaps due to budgetary constraints in the sequel series, Earth was ulimately revealed to be the contemporary one.