Google defines (citing Oxford Languages) offworld as:

* away from earth or (in science fiction) from a place treated as the native world.

* involving, located in, or coming from a place outside one's native world or planet.

While Wiktionary defines it as:

* (chiefly science fiction) Not on Earth.

* (chiefly science fiction) Away from Earth.

https://en.wiktionary.org/wiki/offworld

To me that sounds like Mars would qualify