.AT 17 moments and 40 secs past eight in the evening, Greenwich Mean Time, on July 20th it will certainly be actually precisely 55 years given that Neil Armstrong landed on the Moon. Those 55 years add up to 20,089 days. Of those, 20,062 were 86,400 secs long and 27 one 2nd longer due to the addition of jump seconds, a practice begun in 1972. So those 55 years are going to add up to 1,735,689,627 seconds.