Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Life on Mars? Brown-led research team says elusive mineral bolsters chances

19.12.2008
Over the last several years, scientists have built a very convincing case that Mars hosted water, at least early in its history. Recent observations from the Mars Phoenix lander and other spacecraft show that the planet still holds vast deposits of water as ice at its poles and in soil-covered glaciers in the mid-latitudes.

What is less known is how much water occupied the red planet and what happened to it during its geological march to the present. Mostly, evidence has pointed to a period when clay-rich minerals were formed by water, followed by a drier time, when salt-rich, acidic water affected much of the planet. Assuming that happened, the thinking goes, it would have been difficult for life, if it did exist, to have survived and for scientists to find traces of it.

Now a research team led by Brown University has found evidence of carbonates, a long-sought mineral that shows Mars was home to a variety of watery environments — some benign, others harsh — and that the acidic bath the planet endured left at least some regional pockets unscathed.

If primitive life sprang up in pockets that avoided the acidic transformation, clues for it may remain.

"Primitive life would have liked it," said Bethany Ehlmann, a Brown graduate student and lead author of the paper that appears in the Dec. 19 edition of Science. "It's not too hot or too cold. It's not too acidic. It's a 'just right' place.'

Finding carbonates indicates that Mars had neutral to alkaline waters when the minerals formed in the mid-latitude region more than 3.6 billion years ago. Carbonates dissolve quickly in acid, therefore their survival challenges suggestions that an exclusively acidic environment later cloaked the planet.

The carbonates showed up in the most detail in two-dozen images beamed back by the Compact Reconnaissance Imaging Spectrometer for Mars, an instrument aboard the NASA Mars Reconnaissance Orbiter. Scientists found the mineral near a trough system called Nili Fossae, which is 667 kilometers (414 miles) long, at the edge of the Isidis impact basin. Carbonates were seen in a variety of terrains, including the sides of eroded mesas, sedimentary rocks within Jezero crater and rocks exposed on the sides of valleys in the crater's watershed. The researchers also found traces of carbonates in Terra Tyrrhena and in Libya Montes.

NASA's Phoenix Mars Lander recently found carbonates in soil samples, and researchers had previously found them in Martian meteorites that fell to Earth and in windblown Mars dust observed from orbit. However, the dust and soil could be mixtures from many areas, so the origins of carbonates have been unclear. The latest observations indicate carbonates may have formed over extended periods on early Mars and also point to specific locations where future rovers and landers could search for possible evidence of past life.

"This is opening up a range of environments on Mars," said John "Jack" Mustard, a Brown professor of geological sciences and a co-author on the Science paper. "This is highlighting an environment that to the best of our knowledge doesn't experience the same kind of unforgiving conditions that have been identified in other areas."

The researchers, including Brown graduate student Leah Roach and scientists from NASA, the Johns Hopkins University Applied Physics Laboratory, the Institut d'Astrophysique Spatiale at the University of Paris, the U.S. Geological Survey, Cornell University and the University of Nevada, have multiple hypotheses for how the carbonate-bearing rocks were formed and the origin of the water that shaped them. They may have been formed by slightly heated groundwater percolating through fractures in olivine-rich rocks. Or, they may have been formed at the surface when olivine-rich rocks were exposed and altered by running water. Yet another theory is the carbonates precipitated in small, shallow lakes. Either way, such environments would have boded well for primitive life forms to emerge.

"We know there's been water all over the place, but how frequently have the conditions been hospitable for life?" Mustard said. "We can say pretty confidently that when water was present in the places we looked at, it would have been a happy, pleasant environment for life."

Richard Lewis | EurekAlert!
Further information:
http://www.brown.edu

More articles from Physics and Astronomy:

nachricht One-way roads for spin currents
23.05.2018 | Singapore University of Technology and Design

nachricht Tunable diamond string may hold key to quantum memory
23.05.2018 | Harvard John A. Paulson School of Engineering and Applied Sciences

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Research reveals how order first appears in liquid crystals

23.05.2018 | Life Sciences

Space-like gravity weakens biochemical signals in muscle formation

23.05.2018 | Life Sciences

NIST puts the optical microscope under the microscope to achieve atomic accuracy

23.05.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>