The details were downloaded from the event data and forward-facing video recorders on a NJ Transit commuter train.
Federal investigators also say the train's engineer hit the emergency brake less than a second before the crash.
The speed limit for the station area is 10 mph.
The NTSB says the train was traveling at 8 mph and sped up for about 30 seconds before hitting 21 mph.
A final report on what caused last week's crash, which killed one person and injured more than 100, could take a year or longer to complete.
Meantime the damaged commuter train was removed from the terminal.
It isn't known when service will be restored at the terminal.
