This year, I had the great honour of meeting a man who made a journey that inspired millions across the world. He and his 11 colleagues proved what happens when vision, courageous and determination are focussed on a single goal. The man I met is called Gene Cernan – an astronaut. He was the last human to leave footsteps on the moon.

You probably know the FIRST astronaut to have stood on the moon, on 20th July, 1969, was Neil Armstrong. Standing on that airless orb, he uttered the immortal words: ‘that’s one small step for man, one giant leap for mankind.’ That moment lives as a seminal moment in the history of our species. It symbolised all that is best about our curious, brave and restless spirit.

As Gene Cernan spoke of his experiences, the assembled audience of politicians and public sat enthralled. We were collectively engaged and inspired by the words of the only human of all time to have descended close to the surface of the Moon twice – once in Apollo 10 and then on the final moon mission, Apollo 17.

My grandfather, Ernst Öpik, was a professional astronomer. He played his part in working out whether lunar landers would sink into an ocean of moon dust – a very real concern at the time. Human spaceflight has always been a passion, and the Apollo astronauts hold exalted status for me because of this. To meet these people feels like an honour I find it hard to put into words.

This is why I worry about our current mind-set as a society. Have we lost some of the courage needed to continue this adventure? Do we fear the expenditure – and attacks from those who demand the money be spent instead on social programmes and health – and all the things which occupy politicians on ordinary days when nobody is walking on the moon?

I believe it is our duty to continue the mission to explore space and seek answers to the big questions about the universe and our place within it. Our goal cannot be simply to support a social agenda which keeps us comfortable and in reasonable health. Those things are important, but if we start thinking they’re the reason we’re here we’re missing the point. Our inquisitive nature demands more than that.

In the Apollo missions, Gene Cernan and his fellow astronauts came in peace for all mankind. If we lose our travelling spirit, then a key element in our voyage of discovery as citizens of this cosmos ends too.