Sydney Space Frontier Society's July ZOOM presentation

Date:   Monday July 12, 2021
Time:   7:30 pm Eastern Australian time.
Speaker: Dr Graziella Caprarelli, University of Southern Queensland
“The search for water on Mars”

The discovery of liquid water on Mars continues to be one of the principal objectives of space exploration. Water is the most valuable resource for future human settlements and, even more importantly, it is an essential ingredient for the emergence of life as we know it. The search for liquid water on Mars started in the late 1800s, when Schiaparelli first, and Lowell later, observed and catalogued long linear features on the surface of Mars that Lowell defined “channels”. Whether natural (as Schiaparelli thought) or human-made (as Lowell believed), these were initially thought to be waterways, raising the prospect of a planet similar to Earth. Spacecraft observations soon dispelled this notion, when the Mariner missions revealed a dry and desolate expanse. However, mounting evidence from subsequent space missions to Mars has progressively revealed that Mars was different in earlier times, and while the freezing global surface temperatures are not conducive to water being in a liquid state, geological and astronomical evidence indicates that under certain conditions water could have been liquid, even if for short periods of time, in the past. At present, only hypersaline aqueous solutions can remain liquid, with brines inferred to explain seasonal linear features at mid-latitudes, and, recently, bright radar reflections acquired by the ground penetrating radar (MARSIS) on board of ESA’s mission Mars Express. In this talk Dr Caprarelli will take us on a journey of discovery at the search for evidence of liquid water on Mars, past and present