Scientists are on the hunt for what could be humankind’s greatest discovery: evidence of life on other planets. And they need all the tools they can get. NASA has created an ambitious astrobiology programme, but it may not be enough. What if extraterrestrial life existed in the past and has since vanished? What is needed is a way to identify alien fossils – the new field of astropalaeobiology.
Finding alien fossils is a daunting task. It’s easy to recognise dinosaur skeletons as fossils because only life can sculpt such large, complex objects. It’s much harder to prove that a microscopic object…
