2015 David Cooper Memorial Lecture

Professor Malcolm Walter will deliver this year's David Cooper Memorial lecture as part of the Australian Space Research Conference.  The lecture will be held at 7pm at the Australian National University at 7pm.  For further details including how to book a free ticket, click here.  Download a lecture flyer (pdf).  The title and abstract for the talk are as follows.

THERE IS LIFE ON MARS… PROBABLY

Professor Malcolm Walter

Australian Centre for Astrobiology, UNSW

It is difficult to imagine any greater goal for science than searching for life beyond Earth. Everything we know about life is based on a sample of one: life on Earth. We can only imagine the consequences of discovering life elsewhere, provided it had a separate origin. That, ultimately, is why we are exploring Mars.

As recently as the 1950’s it was thought by serious scientists that there could be advanced forms of life on Mars – not little green people but ferns and other vegetation. That was because seasonally changing patterns of colour had been observed from Earth-based telescopes. We now know that these result from seasonal dust storms. And of course modern imagery reveals there are no canals, pyramids, or faces. So now the search for life on Mars focuses on microbes.

Mars Science Laboratory, Curiosity, is one of the latest in a long series of missions to Mars that started in 1960 with launches by the former Soviet Union and then later the USA.  The first successful mission was NASA’s Mariner 4 that was launched on the 28 November 1964, half a century ago. More recently the European Space Agency has launched very successful missions, joined recently by the Indian Space Agency, and the Japanese have also joined the quest. There have been more than 40 attempted missions about half of which were successful at least to some extent.

NASA’s two Viking missions in the 1970’s were the first, and still the only, explicitly to search for life on Mars. For some the results were equivocal but most consider that no evidence for life was found. Maybe that was because the landing sites were frigid deserts, or maybe the instruments were not sensitive enough, but in any event the consensus is that there were no positive detections.

Nonetheless, from the wealth of data from the successful missions we know that there could be life on Mars. The hints are accumulating. Recent detections of methane are intriguing.

If there was ever life on Mars it will still be there. I think that we are on the verge of a discovery. If it were up to me I would send scientist/astronauts to Mars now, to carefully selected sites. Former hot springs are by far the most prospective sites. We already know where they are. What are we waiting for?

WALTER, M. R. & DESMARAIS, D., 1993 - Preservation of Biological Information in Thermal Spring Deposits: Developing a Strategy for the Search for Fossil Life on Mars. Icarus 101, 129-143.

WALTER, M. R., 1996 - Ancient Hydrothermal Ecosystems on Earth: a New Palaeobiological Frontier. pp.112-127 In Evolution of Hydrothermal Ecosystems on Earth (and Mars ?). Wiley, Chichester (Ciba Found Symp 202).

WALTER, M. R. 1999 - The Search for Life on Mars. Perseus Books (US), Allen & Unwin (Australia), 170p.