Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Down That Long Dusty Trail


While Mars can claim some unique features - the largest volcano and the deepest canyon in the solar system - its rocky, dusty, cold landscape has yet to yield signs of the ultimate prize: life.

Three simple words - follow the water - have become the mantra of astrobiologists studying the Red Planet because the presence of water is believed to be a prerequisite for life, either past or present.

But as scientists look for evidence of water on Mars, they are faced with an underlying dilemma: Will they know life when they see it?

“Scientists’ approach to finding life is very earth-centric,” said Kenneth Nealson, holder of the USC Wrigley Chair in Environmental Sciences. “Based on what we know about life on Earth, we set the limits for where we might look on other planets.”

In a paper published in the current edition of the journal Astrobiology, Nealson - and Bruce Jakosky of the University of Colorado - speculated that a microbe that exists in the coldest temperatures on Earth might provide clues about how a similar organism could survive beneath the Martian polar ice caps.

The microbe in question was discovered by Corien Bakersman, a postdoctoral student in Nealson’s lab, and remains the only one of its kind. It was isolated from a cryopeg - a small, salty, liquid lake found under the Siberian permafrost.

The bacteria, named Psychrobacter cryopegella, can grow at -10 Celsius and can stay alive and even keep metabolizing at an astonishing -20 Celsius While it isn’t able to replicate itself at that extreme temperature, it maintains the minimal metabolism needed to repair and maintain its cell structures.

“This organism can exist at colder temperatures than any previously discovered,” said Nealson, a professor of earth sciences and biological sciences in the USC College of Letters, Arts and Sciences.

“We know it’s possible here, so certainly it’s possible somewhere else. This bacteria expands the limits of life, so if you can find places on Mars that are minus 20 degrees centigrade, you should take a look.”

Nealson and Jakosky looked to the Martian polar regions for a habitat similar to the one in which cryopegella survives.

While temperatures at Mars’ equatorial and mid-latitudes regularly rise above -20 Celsius, it is unlikely that there is liquid water there because of its potential to be absorbed into the atmosphere, Nealson said.

But, liquid water could be found under the frozen polar caps, he added.

Climate changes on Mars, as with all of the nine planets that orbit the sun, are tied to its obliquity, or tilt of its axis with respect to its orbital plane.

Nealson and his colleagues proposed that as the Red Planet tilted - exposing more of itself to the sun at various times in its history - temperatures at the polar ice caps were warmed to minus -20 Celsius or higher.

“If the ice at the polar caps warmed to liquid water, organisms like cryopegella could have awakened and repaired any damage that might have occurred to their various cellular components,” Nealson said.

“Then, as the obliquity changed a few million years later and the planet got colder and colder, these organisms would have been the last survivors.”

But, he added, “I would never say, ‘Go and look for this bacteria.’ I would say, ‘This is a habitat that we should look at on Mars because on Earth, similar habitats have life.’”

The paper’s other contributors were USC’s Corien Bakerman and the University of Colorado’s Ruth Ley and Michael Mellon.

Usha Sutliff | USC News Service
Further information:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>