On 14 May 1838, eighteen-year-old George Williams was indicted and convicted at the Old Bailey in London of stealing one handkerchief to the value of two shillings. Sentence: transported for ten years.

Exactly 23,957 days later, on 17 December 1903, a few miles south of Kitty Hawk in North Carolina, Orville Wright piloted the Wright Flyer on the world’s first sustained powered flight. The aircraft travelled 37m at 11 km/h and at an altitude of 3m. Orville’s brother Wilbur ran alongside.

And 23,957 days after that, on 20 July 1969, Neil Armstrong and Buzz Aldrin threaded the Apollo 11 lunar module Eagle through a boulder field to a safe landing on the Sea of Tranquility.

Sixty-five years and seven months elapsed between the Flyer lifting off from its starting rail and Eagle’s landing pads settling into the grey lunar regolith whipped up by the exhaust of the descent engine. This time between first takeoff and first landing was a period of rapid and significant technological growth, in no small part due to wars. I wonder whether history will ultimately christen it the Flyer/Eagle Delta or some such name.

These arbitrary time periods fascinate me: that we can make such a giant leap, so to speak, easily within the span of one life. That someone, many people, almost certainly watched Armstrong step onto the lunar surface while thinking back to when they first heard about the Wright brothers, or first saw a boxy wooden craft steer hesitantly above them.

It’s illuminating to place the Flyer/Eagle Delta onto other time periods and see how humanity fared: hence the opening to this post. Poor George Williams, nicking a grubby handkerchief and being sent to Australia for his trouble, exactly one delta before the first flight. I wonder, did he live to hear of the Wright Flyer at Kitty Hawk? He’d have been 83 or thereabouts, perhaps returned from Australia. He’d have lived through the rise of the railways, the telegraph and telephone, the US Civil War and Abraham Lincoln, Gladstone and Disraeli, Dickens and Brunel and Darwin, and Queen Victoria’s reign.

The next natural place for the delta: ending today, 7 February 2013. That makes its starting point 7 July 1947. Has humanity made such great progress since that time? In computing, certainly, from huge, clunking code-breakers to smartphones and the internet. In the time since World War II we have become global broadcasters, trackable and instantly contactable almost anywhere on the planet. We’ve increased pollution and population, too, and our ability to destroy ourselves by slow and fast means: but we’ve also made great strides in medicine. We’ve wiped out smallpox and almost wiped out polio. Do the changes feel as momentous as those between 1838 and 1903, or between 1903 and 1969? Not to me. But perhaps a delta feels different from within: we are frogs boiling slowly in the pan, and don’t notice the change.

And now let’s consider the delta that started when Armstrong stepped onto the moon’s surface. When does that end? Add 23,957 days and you reach 21 February 2035: twenty-two years from now. We’re 1947 to Apollo’s 1969, a few months before the first flight to break the sound barrier. We’re 1881 to the Wright brothers’ 1903, just weeks after the gunfight at the OK Corral.

To be precise, we’re 15,908 days into a delta: just under two-thirds of the way. And Thursday 11 April 2013 marks exactly two-thirds of the delta between Apollo 11 and… what? I can’t wait to find out.