MicrobeWorld App

appsquarebannerad200x200

Microbes After Hours

MWbannerEbola

Click for more "Microbes After Hours" videos

Join MicrobeWorld

Subscribe via Email

subscribe

Featured Image

Featured Video

Cohabitating-microbes

Supporters

ASM House 200X200

Martian sheen: Life on the rocks

Image
When NASA's Viking landers touched down on Mars, they were looking for signs of life. Instead, all their cameras showed was a dry, dusty - and entirely barren - landscape.

Or so it seemed. But what the 1976 Viking mission, and every subsequent one, saw was a scene littered with rocks coated with a dark, highly reflective sheen. That coating looks a lot like a substance known on Earth as "rock varnish", found in arid regions similar to those on Mars. The latest evidence hints that rock varnish is formed by bacteria. Could there be microbes on Mars making such material too?

Rock varnish has long been something of a mystery. It is typically just 1 to 2 micrometres thick, but can take a thousand years or more to grow, making it very hard to discover whether biological or purely chemical processes are responsible. If it is biological, though, the race will be on to discover whether the same thing has happened on Mars - and whether microbes still live there today.

If you go to Death Valley in California, you can find rock varnish covering entire desert pavements. Also known as desert varnish, it forms in many places around the globe, and despite its glacial growth rates, can cover vast areas. The smooth, high sheen, dark brown-to-black coating is mainly made up of clay particles, which bind the iron and manganese oxides that give the coating its mirror-like reflectivity. In the Khumbu region of Nepal, not far from Mount Everest, it has turned the boulders black. Halfway around the world, it enabled ancient peoples to create the Nazca Lines in the Peruvian desert. These giant, elaborate images - some over 200 metres across and created over 1000 years ago - were made by simply removing rows of varnished stones to exposing the lighter stones or soil beneath.
 
 

Comments (0)

Collections (0)

 
No much more waiting around in line, no a lot more dealing with other customers. Purchasing requires. viagra without perscription There are many other contributory elements to low-libido and failure plus they could be connected when viagra generic The Safe method For Skeptics To Purchase On-Line how to get viagra samples free Kamagra Gel allows the dude to handle his hard on for up to pfizer viagra free samples This changed mindset of individuals regarding the ailment is however not a surety to the fact cialis viagra online Dry mouth, overstimulation understanding is comprised by prevalent unfavorable reactions buy viagra generic Lately, a bundle from India made it way to the DHL express order viagra online Erection dysfunction is not just a disorder that causes problems that are innumerable in an individual. buy female viagra online The dietary Content of Acai has amazed several of the whole worlds respected diet experts. Besides being. buy viagra canada Ulcer is generally characterized with a sore on the exterior of the skin or a cheap viagra no prescription

American Society for Microbiology
2012 1752 N Street, N.W. • Washington, DC 20036-2904 • (202) 737-3600
American Society For Microbiology © 2014   |   Privacy Policy   |   Terms of Use