Following the mysterious disappearance of Malaysia Airlines flight MH370 last year, the United Nations agreed to use global satellite tracking for passenger airliners. Under the terms of the deal, nations can use specific radio frequencies to monitor planes via satellite rather than solely relying on radar-driven technology on the ground. With a target of 2017, aircraft capable of sending Automatic Dependent Surveillance-Broadcast (ADS-B) signals to the ground will also communicate with satellites to track their movements. Shortly after the MH370 tragedy, Inmarsat offered airlines free satellite tracking for more accurate location info. With this week's agreement, the UN aims to keep an eye on the 70 percent of the world's surface than the ground-based systems can't cover. In theory, the use of satellite tracking would reduce the chance of another flight disappearing without a trace.

[Image credit: Kevin Frayer/Getty Images]