Mathematics – Logic
Scientific paper
Dec 2008
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008agufm.p43d..01b&link_type=abstract
American Geophysical Union, Fall Meeting 2008, abstract #P43D-01
Mathematics
Logic
5215 Origin Of Life, 5410 Composition (1060, 3672)
Scientific paper
Following the OMEGA/Mars Express pioneering discovery of hydrated phyllosilicates in a variety of sites spread over the ancient terrains, an impressive set of results, combining refined observations by OMEGA/Mars Express and CRISM/MRO, relevant contextual images by HRSC/Mars Express and HiRiSe/MRO, modeling and simulations, has been acquired. They confirm the initial hypothesis that these minerals record an ancient era during which water might have remained liquid over extended durations, which led to naming this era: phyllosian. It is remarkable that 30 years after the Mariner and Viking images of Mars as a desolated and inhospitable world, a new vision is emerging, for Mars to have possibly hosted environmental conditions favoring the presence of a key ingredient of potential astrobiological relevance. If ever Mars was habitable, it happened during the phyllosian. A variety of coupled information, from compositional, geomorphological and magnetic data, enables to assess the processes that took place, and their chronology. The observations that we will discuss include the specific composition identified, in relation to the stratification observed; the scarcity of phyllosilicates within the cratered terrains where mafics dominate; the large depth of deposits in a variety of sites, in particular within Mawrth Vallis; the distribution of remnant magnetization, with almost none within the large impacts and along the volcanic features. As a consequence, it will be shown that this era is tightly limited in time. It seems to have ended prior to the heavy bombardment to have ceased: the Noachian expanded long after the phyllosian ended. This habitable era could have been enabled by the maintenance of an active dynamo: its drop triggered its end, given the properties of the early Sun, by the lost of suitable atmospheric conditions for surface water to remain stable as a liquid. Up to now, neither with the Moon or any other body, we did not have means to study the complex history of inner planets along their first hundreds of millions years, at a time when the early bombardment took place, while maintaining habitable conditions which, at least on the Earth, led to the emergence of life. Did the impact rate steadily decreased, or did it drop a number of times, up to late events some 3.8/3.9 billion years ago, offering quiet epochs with biologically active standing water reservoirs in place? Mars is unique in offering means to study this era, as its history preserved sites recording this era with potentially biorelics still in place. The occurrence of phyllosilicate-rich sites offers the exciting perspective to address scientifically the question of the emergence of life elsewhere than on the Earth, and to decipher the processes that drove diverging evolutionary pathways for Mars and the Earth.
Bibring J.
Omega T.
No associations
LandOfFree
Mars habitability: epochs, processes, remnants does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Mars habitability: epochs, processes, remnants, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mars habitability: epochs, processes, remnants will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1238667