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If Your Time is short
The "T" in a "T Minus" countdown simply stands for "time" or "test."
When NASA uses the term "T Minus" during a launch countdown, is it secretly invoking the name of the devil? A social media post suggests as much, but it’s wrong.
"Have you ever wondered why NASA always starts their countdown with T minus…? They are mocking everyone with disclosing in plain sight the letter T subtracted from their name… The same title given to the father of all lies… SATAN," said the first slide in a May 3 Instagram post. It featured an edited photo of the NASA logo which rearranged the letters and added a T so that it reads "SATAN."
The post was flagged as part of Meta’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Meta, which owns Facebook and Instagram.)
"T Minus" does not mean anything demonic. The "T" in "T Minus" stands simply for "time" or "test."
NASA, or the National Aeronautics and Space Administration, has multiple types of countdown besides "T Minus," including "L Minus" and "E Minus."
"E Minus" — with the "E" short for "encounter" — is used for noteworthy mission events when a spacecraft is already in space. "L Minus" and "T Minus" are used for launching rockets.
The National Environmental Satellite, Data, and Information Service explained that L minus — with the "L" meaning "launch" — refers to the time remaining in a scheduled countdown to launch.
Meanwhile, T minus refers to "the time remaining on the official countdown clock." The T-time stops during planned pauses in the countdown process, or when the countdown clock is intentionally stopped. The L-Time continues to advance during pauses in the countdown process.
However, in 2006, Mike Leinbach, the final space shuttle program launch director at NASA’s John F. Kennedy Space Center, said the "T" in "T Minus" stands for "test" because it’s not always related to time. It is also described as a "sequence of events that are built into the launch countdown."
Whether it means "time" or "test," it does not refer to Satan. We rate this claim Pants on Fire!
Instagram post, May 3, 2023
NASA’s Launch Services Program tweet, March 1, 2022
NASA STEM Innovation Lab, Parker Solar Probe: T Minus 2 days, Aug. 8, 2018
NASA, NASA Mission 'E-Minus' One Month to Comet Flyby, accessed May 4, 2023
National Environmental Satellite, Data, and Information Service, Top 5 Terms You Should Know for a Satellite Launch, Nov. 15, 2016
NASA, Artemis I Launch Countdown 101, accessed May 4, 2023
NASA, Transcript: NASA Launch Director Mike Leinbach on Discovery's Launch and Mission, June 28, 2006
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