How the New York Times verified the Iran missile-strike footage

From the link:

On January 8, Ukraine International Airlines Flight 752 caught fire in the sky above Tehran. All 176 people on board the flight died in the incident, the cause of which was not immediately known. The next day, the New York Times published a 20-second video clip which showed the explosion was caused by an Iranian missile. The video refuted statements by Iranian officials that such a cause was “scientifically impossible.”

“We first learned that it was a missile that took down a Ukrainian airliner over Iran because of this video showing the moment of impact,” a Times staffer explained in subsequent coverage