posted 07-23-2019 03:16 PM               

The night of the moon landing, NASA told the press that Armstrong had stepped onto the lunar surface at 10:56:20 p.m., and The New York Times reported that same time stamp on its front page the next morning. The real-time transcription of the mission's air-to-ground voice transmission suggests that Armstrong took the step sometime between 10:56:43 and 10:56:48. And when NASA's official Apollo 11 mission report went public in November 1969, it pinpointed first contact at five seconds earlier, at 10:56:15.

Experts agree that the time NASA fed reporters is probably the least reliable of the bunch. And they don't put much stock in the air-to-ground transcript, a document rife with human error. Some even question the mission report, which incorporated months of data analysis and debriefings with the crew.

...Eric Jones, a former Los Alamos National Laboratory researcher who founded the Apollo Lunar Surface Journal, concluded after conducting an investigation modeled on [space enthusiast Heiko] Küffen's that first contact occurred at 10:56:17. NASA's sticking with its November 1969 mission report: If there's an official time, Barry said, it's 10:56:15.