Tomorrow  I celebrate my time on Earth over the course of 63 circuits of our Sun. It is no small feat in human terms, historically at least, but I get some reassurance at the total mileage of 59,220,000,000 kms. The annual distance is 940 million kms, which looks pretty impressive on any old odometer.

This pales when one starts to look deeper and these localised figures become less impressive. The Sun itself (and our Solar System) takes about 225-250 million years to do a circuit of the centre of the Milky Way, so the last time we were roughly in this spot, dinosaurs were only just beginning to emerge as a class of reptiles. Using the same time scales, said dinosaurs were about to be wiped out at about the three-quarter mark.

I could of course, just settle for a plain old year of 365.25 days and forget the cosmic scales. But somehow the latter is strangely reassuring. Whatever happens today, good or bad, will be forgotten many times over when we swing around next time.