No, this blog post is not about conspiracy theories connected to the Apollo program, Apollo 11, or the moon landing. Instead, it is about an alternate universe in which the first moon landing had a less fortunate ending, a “there but for the grace of god” in reverse.
The day: June 20, 1969, around 6 p.m. UTC (Coordinated Universal Time).
Neil Armstrong and Edwin ‘Buzz’ Aldrin have 
successfully landed on the moon, completed their famous moon walk, taken photographs, collected about 20 kg worth of lunar rock and soil samples, and have finally re-entered Eagle (as they named their lunar lander). They’ve slept for a good seven hours, and, now that they are both awake again, the time has come to lift off from the moon, to get back into lunar orbit, rendezvous with Columbia, where their crewmate Michael Collins is awaiting their return, and to, ultimately, head back to earth.
So Armstrong and Aldrin fire the Eagle’s engine.
And … … … nothing happens.