Is it possible to patent across geographical locations, even if I am not physically in all the locations?
Yes. A patent application that is lodged under the World Intellectual Property Organization's PCT (Patent Cooperation Treaty), can be lodged in any WIPO approved receiving office (including US, Australia, Europe etc) and can be designated to convert later into national patents at your cost and burden, while retaining the priority data and disclosure of the original filing.
So for instance a single filing of a PCT Application (this one is from a Monsanto invention), gave rise to both granted patents later (after payment of fees, sometimes including translations, and examination and allowance) and to further applications in national offices.
The non-profit Cambia & The Lens offer tutorials and help pages that you may find useful. The World Intellectual Property Organization, a UN Organization that administers the PCT also has many useful resources.