The Malaysian government has concluded that, based on satellite data analysis from British company Inmarsat, Malaysian Airlines flight MH370 ended in the Indian Ocean, and no one on board survived.
The Telegraph reports on Inmarsat and how it was used in the tracking:
Inmarsat’s role in the search for Malaysian Airlines flight MH370 began immediately after the aircraft disappeared. Although the main aircraft communications addressing and reporting system (which would usually transmit the plane’s position) was switched off, one of Inmarsat’s satellites continued to pick up a series of automated hourly ‘pings’ from a terminal on the plane, which would normally be used to synchronise timing information.
CNN.COM also has an easy-to understand explanation of how the jet’s path was tracked.