Search for Life on MARS

Q: Why is water important for life? A: Because it’s such a great solute.

Who am I? Adrian BrownAdrian Brown PhD student at the Australian Centre for Astrobiology (ACA), Macquarie UniversityPhD student at the Australian Centre for Astrobiology (ACA), Macquarie University Supervisors are Prof. Malcolm Walter, Director of the ACA, and Dr. Tom Cudahy, CSIROSupervisors are Prof. Malcolm Walter, Director of the ACA, and Dr. Tom Cudahy, CSIRO Thesis topic – Mapping Ancient Hydrothermal Systems on Earth and MarsThesis topic – Mapping Ancient Hydrothermal Systems on Earth and Mars

Presentation Overview Finding water in rocksFinding water in rocks Colours of ancient rocks – Pilbara, WAColours of ancient rocks – Pilbara, WA NASA’s Mars Exploration LandersNASA’s Mars Exploration Landers 2004 Mars Landing Sites – how they were chosen2004 Mars Landing Sites – how they were chosen Rover InstrumentsRover Instruments –Colours of ancient rocks – Gusev Crater, Mars –Investigating Grains of Rock with Microscopes –Dust: part of the problem or the solution?

H Finding water in rocks! Water becomes part of rocks in various ways:Water becomes part of rocks in various ways: –Unbound water, fluid inclusions –Bound water in clays –Part of the mineral, in the form of hydroxyl It can be preserved in these forms indefinitely, but will be subject to weathering, radiation (evaporation), diffusion and advection processesIt can be preserved in these forms indefinitely, but will be subject to weathering, radiation (evaporation), diffusion and advection processes O H

Ancient Rocks of Earth – a Mars Analogue? ACA scientists are investigating the ancient Pilbara region of northern Western AustraliaACA scientists are investigating the ancient Pilbara region of northern Western Australia 3.5 billion years old3.5 billion years old Contains first signs of life on Earth in the form of stromatolitesContains first signs of life on Earth in the form of stromatolites Could be a good analogue for MarsCould be a good analogue for Mars

North Pole Dome

Colours of Ancient Rocks A spectrometer splits up light into different coloursA spectrometer splits up light into different colours By graphing colour intensities we can record a characteristic spectral response of rocksBy graphing colour intensities we can record a characteristic spectral response of rocks Rock Sample Sun Diffractometer Collector Infrared Red Yellow Blue Ultraviolet

Colours of rocks Mica alteration (left) chlorite alteration (right)Mica alteration (left) chlorite alteration (right)

Mapping colours of rocks

The 2003 Martian Missions

Mars Exploration Rovers (MER)

Landing Site Restrictions Low latitudes required because the rovers are solar poweredLow latitudes required because the rovers are solar powered Landing site must be 1.3km below ‘Martian Sea level’ so parachutes can functionLanding site must be 1.3km below ‘Martian Sea level’ so parachutes can function Low winds must be presentLow winds must be present Not too much dust, lest solar arrays and rocks are covered, and surface must bear the weight of a roverNot too much dust, lest solar arrays and rocks are covered, and surface must bear the weight of a rover Just enough rocks to be interesting, not enough to be dangerousJust enough rocks to be interesting, not enough to be dangerous

GusevIsidisMeridiani

MER Instruments APXS – alpha particle x- ray spectrometer Mossbauer – fe spectrometer MI – microscope imager RAT – rock abrasion tool PANCAM – panoramic camera Mini TES – thermal emission spectrometer Magnetic Arrays

Colours of rocks on Mars Silicates Carbonates CO 2

Dust – part of the problem or solution?

Latest image