It was with great sadness that I heard of the death of Neil Armstrong just as I arrived in Manchester to visit family on Aug. 25.
Alas, I wasn't born until 1973 so missed all of the Apollo moon landings and the incredible achievements of not only Neil, but Buzz Aldrin, Michael Collins and NASA's ground crew plus thousands of individuals who made Apollo 11 happen.
I was invited to a BBC Radio 5live broadcast that evening and the following Sunday morning to a couple of BBC TV channels to speak. I think each interview included the question about my thoughts about the legacy of Armstrong.
The answer was simple; even to someone born four years after the first step onto the surface of the moon, it still served as an inspirational moment and one that could inspire people for decades to come. There aren't many events in human history that can claim that.
In the days that followed after the flurry of interviews, it dawned on me that Armstrong leaves an even more physical and profound legacy and it has its origins back on the surface of the moon, just over quarter of a million kilometers away.
Like most of the natural satellites in the solar system, the moon has no appreciable atmosphere and what little atmosphere is there has no appreciable impact. There is no wind, no rain and as a result no corrosion of the lunar surface.
This means anything that changes the surface of the moon will stay there until it gets changed by some geological or external force. When Armstrong stepped off the ladder attached to the lunar module "Eagle," he left on the surface an imprint of the sole of his boot. That imprint is still there today and will remain there for at least another million years.
Images beamed back from NASA's Lunar Renaissance Orbiter (LRO) show the landing sites of many of the Apollo missions and the tracks etched into the dusty lunar surface by the various lunar rovers and astronauts' bootprints.
It's tantalizing evidence that the remnants of the Apollo missions will be left untouched for eons so future space explorers can visit the sites. Just think, where will humans be in the next million years? Maybe school children will be able to take day trips to the Moon for history lessons and be able to see, first hand, the amazing and immortal boot print where the first human walked on another world.
That is a legacy worthy of one man, of Neil Armstrong, the first human ambassador to the solar system.