Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Was there life on Mars? Shiny rock coating may hold the answer

03.07.2006
A mysterious shiny coating found on rocks in many of Earth’s arid environments could reveal whether there was once life on Mars, according to new research.

The research, published in the July edition of the journal Geology, reveals that the dark coating known as desert varnish creates a record of life around it, by binding traces of DNA, amino acids and other organic compounds to desert rocks. Samples of Martian desert varnish could therefore show whether there has been life on Mars at any stage over the last 4.5 billion years.

The researchers hope that these results will encourage any future Mars Sample Return mission to add desert varnish to its Martian shopping list.

The source of the varnish, which looks like it has been painted onto the rocks, has intrigued scientists since the mid nineteenth century, including Darwin, who was so fascinated that he asked the geochemist Berzelius to investigate it. It was previously suggested that its dark colour was the result of the presence of the mineral manganese oxide, and that any traces of life found within the varnish came from biological processes caused by microbes in this mineral.

However, the new research used a battery of techniques, including high resolution electron microscopy, to show that any traces of life in the varnish do not come from microbes in manganese oxide. The research reveals that the most important mineral in the varnish is silica, which means that biological processes are not significant in the varnish’s formation. On desert rock surfaces, silica is dissolved from other minerals and then gels together to form a glaze, trapping organic traces from its surroundings.

Dr Randall Perry, lead author of the research from the Department of Earth Science and Engineering at Imperial College London, explained that as life is not involved in desert varnish formation, the varnish can act as an indicator of whether life was present or absent in the local environment.

Dr Perry said: “If silica exists in varnish-like coatings in Martian deserts or caves, then it may entomb ancient microbes or chemical signatures of previous life there, too. Desert varnish forms over tens of thousands of years and the deepest, oldest layers in the varnish may have formed in very different conditions to the shallowest, youngest layer.

“These lustrous chroniclers of the local surroundings can provide a window back in time. Martian desert varnish would contain a fascinating chronology of the Martian setting,” he added.

The research was carried out by researchers at Imperial College and the Universities of Auckland (NZ); Wisconsin-Parkside and Washington (US); and Nottingham Trent (UK).

Laura Gallagher | alfa
Further information:
http://www.imperial.ac.uk

More articles from Earth Sciences:

nachricht Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute

nachricht Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>