There are also surveillance blimps, which I believe would be closest to a real-time feed. Some can apparently stay up for 30 days at a time. These have been tes

There are also surveillance blimps, which I believe would be closest to a real-time feed. Some can apparently stay up for 30 days at a time. These have been tested for domestic intelligence, and radar (rather than optical) systems have been deployed overseas. https://www.washingtonpost.com/business/technology/blimplike-surveillance-crafts-set-to-deploy-over-maryland-heighten-privacy-concerns/2014/01/22/71a48796-7ca1-11e3-95c6-0a7aa80874bc_story.html https://www.washingtonpost.com/business/technology/blimplike... https://en.wikipedia.org/wiki/Tethered_Aerostat_Radar_System https://en.wikipedia.org/wiki/Tethered_Aerostat_Radar_System