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Next year, marks half a century since mankind walked upon another world. This year, marks an equally important anniversary. On the 21 December 1968, the crew of Apollo 8 – Frank Borman, Jim Lovell and William Anders – blasted off from the Kennedy Space Center en route for the Moon. Though they didn’t land, they did become the first human beings to see the whole of the Earth, to witness an Earthrise and to venture beyond Earth’s orbit.
However, they weren’t the first Earthlings to go extraterrestrial – that honour belongs not to mankind, but to tortoise-kind. On 18 September 1968, two tortoises, some flies and various other creepy-crawlies were launched into space aboard the Soviet Union’s Zond 5 mission – the first spacecraft to circle the moon and come back home again.
If life has evolved nowhere else in the universe, then that means the history of extraterrestrial life is a mere 50 years old – beginning with a couple of commie tortoises and their invertebrate fellow travellers.
But how likely is it that life is unique to Earth? Not very, one might think. The universe is a big place – and one in which planets not unlike our own are thick as blackberries.
We don’t know how life first arose. We’ve yet to replicate the process in a laboratory. Yet, it must be possible, otherwise we wouldn’t be here. We also have evidence, albeit patchy, that the evolution of intelligence is possible. So, given the mind-boggling number of opportunities for it to happen elsewhere, it would seem exceedingly unlikely that we’re alone.
But how do we calculate the odds? In a fascinating piece for Vox, Liv Boeree writes about the main statistical tool at our disposal – the Drake Equation:
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SubscribeInteresting to see how little humanity cares whether its alone in The Universe or not,
especially with the latest data on encounters between US Naval Aircraft and someone else’s high performance Tic Tac since 2004.