Mark Williams - The Cosmic Oasis

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Mark Williams and Jan Zalasiewicz 2022

Images Anne-Sophie Milon

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Library of Congress Control Number: 2022930602

ISBN 9780198845874

DOI: 10.1093/oso/9780198845874.001.0001

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This book grew out of the way that our workas palaeontologists long fascinated by all that the fossil record can tell us about past lifehas evolved to focus ever more on the revolution that life on Earths life is undergoing today, and on its uncertain prospects for the future. That a book managed to emerge out of this alarmingly wide topic was in no part due to the support, encouragement and marvellously helpful advice from Latha Menon, Jenny Nugee and their colleagues at Oxford University Press.

Among our colleagues in palaeontology and geology who have most shaped our thinking about lifes history have been John Norton, Adrian Rushton, Richard Fortey, David Siveter, Dick Aldridge, Barrie Rickards, Sarah Gabbott, Tom Harvey, Tony Barnosky, Reinhold Leinfelder, Scott Wing, Alan Haywood, Alex Page, Juan Carlos Berrio, Colin Waters, Tom Wong Hearing, Thijs Vandenbroucke, Stephen Himson and Rachael Holmes. Rachael was especially kind in reading an early draft of our manuscript and suggesting many improvements. Our more recent travels beyond our discipline into far wider realms of learning about life writ large have been enabled and guided by Julia Adeney Thomas, Will Steffen, Paul Crutzen, Bruno Latour, Dipesh Chakrabarty, Jacques Grinevald, Davor Vidas, Peter Haff, Bernd Scherer, John Palmesino and Ann-Sofi Rnnskog and Marta Gasparin. It has been quite a journey of discovery, that would have been quite impossible without the kind of education that these colleagues and many others have provided.

For this book, we have worked with the artist Anne-Sophie Milon, whose contribution went far beyond providing a series of inspired images to bring a new kind of life to these pages. She helped shape and guide the text, especially when we drifted too far away from our usual shoresand indeed her marvellous drawings inspired some of our words.

And we are grateful to our families: Asih and Milana, and Kasia, Mateusz and Camille, for their support and infinite patience throughout this long journey, and to our parents, Doreen, Les, Irena and Feliks, for giving us the gift of an interest in life, writ both large and small.

Mark Williams & Jan Zalasiewicz

W hen the Apollo 8 astronaut Bill Anders saw the Earth, half lit and half in darkness and more than 230,000 miles away, rise over the lunar surface, he broke away from the tight NASA schedule to snap its image. He little realized how much that image would affect its human inhabitants. Conditions were almost perfect on that day of 24 December 1968. The side of the Earth that was illuminated, in an almost unbearably poignant symphony of blue sea, brown and green land, and white ice and cloud, contrasted unforgettably with the desolation of the Moons cratered surface. Earthrise, as it came to be called, symbolized, as no image before, the delicacy, fragility, and habitability of our planet as it hangs in endless and hostile space. It became a key element of human awareness of the living, and life-giving, environment that surrounds and sustains us.

Fifty years later, Anders said that he had gone to explore the Moon, but discovered the Earth. It was the space programmes that showed our planet to be an oasis of life within a largely barren cosmos, providing an understanding quite at odds with that of earlier generations of scientists. For it was not so long ago that the Moon could be reasonably supposed to support some kind of life. That celebrated astronomer Sir William Herschel used his magnificently engineered telescope to search for life on the Moon, and in 1778 thought that he had observed lunar towns. By the next century, such speculations were being shown to be increasingly improbable (though that was not to deter such scientifically literate writers as H.G. Wells from incorporating intelligent Selenite civilizations into their stories of mystery and adventure). Nevertheless, even when the NASA Moon missions were being planned, the possibility of some kind of life on the Moonthat could be threatened by arriving humans or that could be a threat to those humanswas seriously considered.

The planning committees for the Moon launch included the visionary space scientist Carl Sagan, who had written part of his PhD thesis on the possibility of organic material thereincluding past or present life. He thought the Moon in its early days originally had water and an atmosphere, in which many complex organic molecules were likely produced, and perhaps even life might have developed, before the weak surface gravity took its toll, and both surface water and atmosphere were lost to space. Great care should be taken with any future astronauts, he warned, so that they are not contaminatedor that they do not contaminate any delicate lunar microbial cultures that might remain.

When the astronauts arrived, they found a lifeless, almost bone-dry wasteland; debate continues on the exact meaning of almost, but for all biological purposes, the Moon is dry. Moreover, the Moons origins are being increasingly seen as dramatic and fiery enoughas the condensed remains of out-flung debris when the early proto-Earth collided with the doomed Mars-sized planet Theiato make notions of any kind of early lunar life highly improbable.

This absolute lunar sterility is now seen, paradoxically, as a potential source of clues to what kind of organic compounds might have existed in the early Solar System. After all, what better place to preserve such primitive organic compounds than a body that is absolutely devoid of life, and thereby possesses no possibility of metabolic reworking of such early organic molecules? On Earth, such molecules have long been caught up and transformed by the all-embracing web of life. And so, just beneath the Moons surface, in places buried deeply enough by meteorite-generated rubble to provide protection from damaging cosmic and solar radiation, there may be a treasure trove of pristine, fossilized organic molecules from the dawn of our planetary system.