After several months of investigation, officials with the National Transportation Safety Board (NTSB) are set to give their verdict on what caused the fatal crash of the Virgin Galactic spaceship last year.
The NTSB is expected to announce why the aircraft broke apart over the Mojave Desert during a test flight in November 2014.
Michael Alsbury, 39, died in the incident, and pilot Peter Siebold, 43, was seriously hurt.
To pinpoint the cause, investigators have considered the quality of training pilots received, whether the rocket was designed to high-enough standards and whether mechanical problems could be to blame.
NTSB officials have already revealed that the co-pilot prematurely unlocked equipment designed to slow the descent of the spacecraft during initial re-entry.
You can watch a live stream of the announcement here.
Virgin Galactic has been undeterred by the crash, and has continued with its plan to build a craft designed for space tourism by developing another ship.
