Up to half of all life on Earth consists of simple microorganisms hidden in rocks beneath the surface and for some time, scientists have suggested that the same may be true for Mars. Now this theory has been supported by new research, which suggests that the ingredients for life have been present in the Martian subsurface for much of the planet’s history.
When meteorites strike the surface of Mars, they act like natural probes, bringing up rocks from far beneath the surface. Recent research has shown that many of the rocks brought up from the Martian subsurface contain clays and minerals whose chemical make-up has been altered by water, an essential element to support life. Some deep craters on Mars also acted as basins where groundwater likely emerged to produce lakes.
McLaughlin Crater, described in this study, is one such basin that contains clay and carbonate minerals formed in an ancient lake on Mars. The fluids that formed these minerals could carry clues to as to whether the subsurface contained life.
“We don’t know how life on Earth formed but it is conceivable that it originated underground, protected from harsh surface conditions that existed on early Earth. Due to plate tectonics, however, the early geological record of Earth is poorly preserved so we may never know what processes led to life’s origin and early evolution,” said Dr Joseph Michalski, lead author and planetary geologist at the Natural History Museum in London. “Exploring these rocks on Mars, where the ancient geologic record is better preserved than on Earth, would be like finding a stack of pages that have been ripped out of Earth’s geological history book. Whether the Martian geologic record contains life or not, analysis of these types of rocks would certainly teach us a tremendous amount about early chemical processes in the solar system.”
Co-author Deanne Rogers, Assistant Professor in the Department of Geosciences at Stony Brook University used data from the Thermal Emission Spectrometer aboard NASA’s Mars Global Surveyor and the Thermal Emission Imaging System aboard the Mars Odyssey orbiter to detect and identify minerals that proved to be consistent with a sustained aqueous environment on the floor of the McLaughlin Crater.
“Our understanding of Mars is changing very rapidly with all of the new mission data,” said Professor Rogers. “There have been several recent observations and models that have pointed to the possibility of a vast store of groundwater in the Martian past, and perhaps present. So you might expect that deep basins such as McLaughlin, which intersect the upwelling groundwater table, would contain evidence of this water. And this study found that evidence.”
Current exploration of Mars focuses on investigating surface processes because sedimentary rocks are most likely to provide the best chance evidence for habitability. Evidence suggests, however, that the Martian surface environment has been quite inhospitable to life for billions of years. In future missions, scientists could choose to target rocks related to the surface or subsurface, or perhaps do both by targeting areas where sedimentary rocks formed from subsurface fluids.
Michalski concludes: ‘In this paper, we present a strong case for exploring the subsurface, as well as the surface. But I don’t personally think we should try to drill into the subsurface to look for ancient life. Instead, we can study rocks that are naturally brought to the surface by meteor impact and search in deep basins where fluids have come to the surface.’
Co-author Professor John Parnell, geochemist at the University of Aberdeen, commented, “This research has demonstrated how studies of Earth and Mars depend on each other. It is what we have observed of microbes living below the continents and oceans of Earth. They allow us to speculate on habitats for past life on Mars, which in turn show us how life on the early Earth could have survived. We know from Earth's history that planets face traumatic conditions such as meteorite bombardment and ice ages, when the survival of life may depend on being well below ground. So it makes sense to search for evidence of life from that subsurface environment, in the geological records of both Earth and Mars. But it's one thing to do that on Earth – we need to be clever in finding a way to do it on Mars.”
Additional co-authors of the study include: Javier Caudros, Researcher, Clay Mineralogy, Earth Sciences Department, Natural History Museum, London; Paul B. Niles, Planetary Scientist, NASA Johnson Space Center; and Shawn P. Wright, Postdoctoral Fellow in Geology, Auburn University.
Deanne Rogers | Source: Newswise
Further information: www.stonybrook.edu
More articles from Earth Sciences:
GPS solution provides three-minute tsunami alerts
17.05.2013 | European Geosciences Union
NASA Sees Eastern Pacific Get First Tropical Storm: Alvin
17.05.2013 | NASA’s Goddard Space Flight Center
Researchers have shown that, by using global positioning systems (GPS) to measure ground deformation caused by a large underwater earthquake, they can provide accurate warning of the resulting tsunami in just a few minutes after the earthquake onset.
For the devastating Japan 2011 event, the team reveals that the analysis of the GPS data and issue of a detailed tsunami alert would have taken no more than three minutes. The results are published on 17 May in Natural Hazards and Earth System Sciences, an open access journal of ...
A new study of glaciers worldwide using observations from two NASA satellites has helped resolve differences in estimates of how fast glaciers are disappearing and contributing to sea level rise.
The new research found glaciers outside of the Greenland and Antarctic ice sheets, repositories of 1 percent of all land ice, lost an average of 571 trillion pounds (259 trillion kilograms) of mass every year during the six-year study period, making the oceans rise 0.03 inches (0.7 mm) per year. ...
About 99% of the world’s land ice is stored in the huge ice sheets of Antarctica and Greenland, while only 1% is contained in glaciers.
However, the meltwater of glaciers contributed almost as much to the rise in sea level in the period 2003 to 2009 as the two ice sheets: about one third. This is one of the results of an international study with the involvement of geographers from the University of Zurich.
Second sound is a quantum mechanical phenomenon, which has been observed only in superfluid helium.
Physicists from the University of Innsbruck, Austria, in collaboration with colleagues from the University of Trento, Italy, have now proven the propagation of such a temperature wave in a quantum gas. The scientists have published their historic findings in the journal Nature.
Below a critical temperature, certain fluids become superfluid ...
Researchers use synthetic silicate to stimulate stem cells into bone cells
In new research published online May 13, 2013 in Advanced Materials, researchers from Brigham and Women's Hospital (BWH) are the first to report that synthetic silicate nanoplatelets (also known as layered clay) can induce stem cells to become bone cells without the need of additional bone-inducing factors.
Synthetic silicates are made ...
17.05.2013 | Physics and Astronomy
17.05.2013 | Physics and Astronomy
17.05.2013 | Physics and Astronomy
17.05.2013 | Event News
15.05.2013 | Event News
08.05.2013 | Event News