This day ten years ago, I was in the American Museum of Natural History in Central Park, Manhattan. At the time, I didn’t realise it was Earth Day and there is probably no better place to spend that day than a museum dedicated to the wonders of Earth and beyond. Among the exhibits was a model of one of the Mars Rovers. Two rovers, Spirit and Opportunity, landed on the red planet in January 2004. Theirs was a 90-day mission of scientific exploration and both machines far exceeded expectations and hope. Spirit was operational for more than 6 years but had fallen silent by the time I stood in front of its facsimile in New York. Opportunity was still trundling about on the other side of Mars and would continue to operate and communicate back to Earth until 2018. Three days ago on Mars, a small helicopter took off and flew for less time than the original Wright Flyer managed in 1903. The helicopter, called Ingenuity, and the first aircraft to achieve powered flight on another planet, was carrying a piece of material from the Wright Flyer, the first aircraft to do the same on Earth 118 years ago.

Happy Earth Day.