Seeking Life on Other Worlds - And What It Means for Life on This One
Monday, 3 September 2012
| Roger Morris
I just love gazing at pictures of Mars. I love reminding myself over and over just exactly what I’m looking at – quite literally the landscape of another world, another mysterious realm of God’s creation. I try to imagine what it must be like to stand there on the Red Planet – despite the minus 100 degrees Celsius snap freeze, the total lack of breathable air, the breath-sucking low atmospheric pressure and the brain-frying cosmic radiation. Even so, I find gazing over the ancient, rust-coloured, pebbly flood plains of Gale Crater totally memorizing. I constantly tell my kids excitedly that maybe in my lifetime, and definitely in theirs, humanity might eventually set foot personally where we have so far managed to land robotic hardware.
Landing the 900kg, car-sized Mars Rover Curiosity (carrying the Mars Science Laboratory – MSL) in Gale Crater on the 6 August, 2012, was an astonishing feet of human scientific knowledge, technological know-how and ingenuity. I will admit to being one of the doubters when I first watched the simulation of the planned landing. So many things could have gone disastrously wrong. Ockham’s razor seemed to have been perilously violated. Much to the amazement of millions, the whole mission went off like fantastic clockwork – the 9 month, 563 million km space flight, the perfectly executed entry into the Martian upper atmosphere followed by the mind-boggling EDL (Entry-Descent-Landing) Phase – nicknamed “The Seven Minutes of Terror” – and the final coming to rest of Curiosity in Gale Crater less than 2.4km from the centre of the planned landing ellipse.
So what are the objectives of this ground-breaking, US$2.5 billion Mars mission?
The MSL mission has four scientific goals as stated by NASA’s Mars Science Laboratory Website:
1. Determine the landing site's habitability including,
2. The role of water
3. The study of the climate and,
4. The geology of Mars.
It is also useful preparation for a future manned mission to Mars. To contribute to these goals, MSL has eight main scientific objectives:
Biological
Geological and geochemical
- Investigate the chemical, isotopic, and mineralogical composition of the Martian surface and near-surface geological materials.
- Interpret the processes that have formed and modified rocks and soils.
Planetary process
Surface radiation
As part of its exploration, it also measured the radiation exposure in the interior of the spacecraft as it traveled to Mars, and it is continuing radiation measurements as it explores the surface of Mars. This data would be important for a future manned mission.
Essentially, a prime objective of this highly detailed study of the Martian environment in Gale Crater is whether life in any form ever got started in the 4.5 billion year deep history of Mars. Astrobiology is the study of the origin, evolution, distribution, and future of extraterrestrial life. This interdisciplinary field encompasses the search for habitable environments in our Solar System and habitable planets outside our Solar System, the search for evidence of prebiotic chemistry, laboratory and field research into the origins and early evolution of life on Earth, and studies of the potential for life to adapt to challenges on Earth and in outer space. Astrobiology addresses the question of whether life exists beyond Earth, and how humans can detect it if it does. Astrobiology makes use of physics, chemistry, astronomy, biology, molecular biology, ecology, planetary science, geography, and geology to investigate the possibility of life on other worlds and help recognize biospheres that might be different from the biosphere on Earth.
So far, Mars reminds us of the “just so” elements of Earth that have allowed life to develop on our home planet. Mars is just a little too small to have enough gravity to hold on to enough atmosphere, to in turn hold on to enough heat to allow liquid water to pool on its surface. As far as we can tell in astrobiology, liquid water is essential for the development of life, at least as we conceive it. This, combined with the fact that it is just a little bit too far away from our sun, means that Mars is a dry, dusty and frigid desert, it seems. Due to its internal planetary structure, unlike Earth, Mars also lacks a magnetosphere which renders the Martian surface vulnerable to bursts of sterilizing cosmic radiation from frequent solar flares and from deep space sources. Compare and contrast this to Earth’s other neighbour Venus which, although closer in size to Earth, is just a little too close to the sun and this combines with can-crushing atmospheric pressure that is 92 times the atmospheric pressure on Earth, a lack of protective magnetosphere to protect the surface from deadly cosmic radiation, and a runaway greenhouse effect resulting in surface temperatures approaching 500 degrees Celsius. All of this should be a sober reminder of the special and unique environment of our home planet, one that I believe was created over 4.5 billion years specifically for us to eventually inhabit by the Great Astrobiologist of the Cosmos. If there is any chance that the human race is contributing to climate change on this planet, and I believe that the evidence for this is extremely strong, surely looking at how much difference the “few degrees of separation” we see with Mars and Venus should prompt us to take these matters extremely (even deadly) seriously. Apart from the “pale blue dot” of Earth floating in the dense blackness of our solar system (as photographed famously by Voyager 1 spacecraft in 1990 from a distance of 6 billion kms), we literally have no other place to go.
And what if MSL actually does find evidence of the development of even simple life on the Red Planet, either currently or in the deep history of the planet? Well, for one, the discipline of astrobiology will go skyrockets, and it will force us all to reconsider our place in the cosmos, as well as our models for human anthropology – both biologically and, without a doubt, theologically. From a Christian perspective I believe discovery of life on Mars would force a radical rethink of Christian theological anthropology. I am confident that the Christian faith would happily survive this crisis of theology, like it has many times before over it’s more than 2000 years of history – but not without first forcing us to rethink some precious tenets of the faith. It would force us to read in a new light what the scriptures are trying to tell us about God’s creative power, and the unique place and role of humanity in this Creation.
Roger Morris runs Faith Interface, a popular blog devoted to the discussion of the interface of the Christian faith with science, philosophy and culture. He has a background in biomedical science and is a Fellow of The Institute for the Study of Christianity in an Age of Science and Technology (ISCAST).