Perchlorates: Mars Chemical Changes Search for Red Planet Life

The Curiosity Rover took this composite self-portrait in the Rocknest sand patch on Mars. Tests of soil at the site suggest that troublesome chemicals called perchlorates are common on the Red Planet.

Credit: NASA

Astronauts sent to Mars on future space missions will have to contend with the toxic and explosive chemical known as perchlorate that's widespread in Red Planet dirt.

Perchlorates have already proved to be problematic for researchers using robotic rovers to hunt for possible traces of Martian life, a new study has found.

As part of its science mission, NASA's Mars rover Curiosity heats up scoops of Red Planet dirt to test for organic carbon compounds — the building blocks of life on Earth.

But that heat can cause perchlorates in soil samples to set off a chemical reaction that destroys organics, researchers discovered.

Daniel Glavin

"The presence of perchlorates isn't good news for some of the techniques currently being used with Curiosity," study lead author Daniel Glavin, an astrobiologist at NASA’s Goddard Space Flight Center in Greenbelt, Md., said in a statement.

"This may change the way we search for organics in the future on Mars."

Perchlorates, which are salts comprised of chlorine and oxygen, were first detected in Martian polar soil by NASA's Phoenix lander in May 2008.

More recently, Curiosity found perchlorates while trekking around the Rocknest sand dune in November 2012.

Curiosity's Sample Analysis at Mars (SAM) system uses a pyrolysis gas chromatograph mass spectrometer, which is an instrument that breaks soil down into its chemical components and measures the concentration of each type of molecule.

But when perchlorates in these soil samples are heated above 392 degrees Fahrenheit (200 degrees Celsius), they release pure oxygen, the researchers say.

This oxygen then causes organic molecules in the sample to combust into carbon dioxide.


However, Glavin said not all of the organic carbon would be destroyed in this reaction; some might be preserved inside more heat-resistant materials, or the molecules could possibly be detected before the breakdown of perchlorates.

Scientists might be able to account for the organic carbon that has combusted if they assume a certain baseline of perchlorate in Martian dirt, he added.

The recent findings at Rocknest could help scientists establish this baseline.

"It will be absolutely critical as we move on to other samples to compare them to the Rocknest dune to infer the presence or absence of Martian organic material," Glavin said in a statement.

Hawaii Astrobiologists find Martian clay contains Chemical Organics

Electron microscope image showing the 700-million-year-old Martian clay veins containing boron (100 µm = one tenth of a millimeter).

Researchers from the University of Hawaii at Manoa NASA Astrobiology Institute (UHNAI) have discovered high concentrations of boron in a Martian meteorite.

When present in its oxidized form (borate), boron may have played a key role in the formation of RNA, one of the building blocks for life.

The work was published on June 6 in PLOS One.

The Antarctic Search for Meteorites team found the Martian meteorite used in this study in Antarctica during its 2009-2010 field season.

The minerals it contains, as well as its chemical composition, clearly show that it is of Martian origin.

Using the ion microprobe in the W. M. Keck Cosmochemistry Laboratory at UH, the team was able to analyze veins of Martian clay in the meteorite.

After ruling out contamination from Earth, they determined boron abundances in these clays are over ten times higher than in any previously measured meteorite.

"Borates may have been important for the origin of life on Earth because they can stabilize ribose, a crucial component of RNA. In early life RNA is thought to have been the informational precursor to DNA," said James Stephenson, a UHNAI postdoctoral fellow.

RNA may have been the first molecule to store information and pass it on to the next generation, a mechanism crucial for evolution.

Although life has now evolved a sophisticated mechanism to synthesize RNA, the first RNA molecules must have been made without such help.

One of the most difficult steps in making RNA nonbiologically is the formation of the RNA sugar component, ribose. Previous laboratory tests have shown that without borate the chemicals available on the early Earth fail to build ribose.

However, in the presence of borate, ribose is spontaneously produced and stabilized.

This work was born from the uniquely interdisciplinary environment of UHNAI. The lead authors on the paper, Stephenson, an evolutionary biologist, and Lydia Hallis, a cosmochemist who is also a UHNAI postdoctoral fellow, first came up with the idea over an after-work beer.

"Given that boron has been implicated in the emergence of life, I had assumed that it was well characterized in meteorites," said Stephenson.

"Discussing this with Dr. Hallis, I found out that it was barely studied. I was shocked and excited. She then informed me that both the samples and the specialized machinery needed to analyze them were available at UH."

More information: 
Stephenson, J. D., Hallis, L. J., Nagashima K., and Freeland, S. J. 2013, "Boron Enrichment in Martian Clay," PLoS ONE 8(6): e64624. dx.doi.org/10.1371/journal.pone.0064624

Mercury: Enhanced Colours of the Innermost Planet

This colorful view of Mercury was produced by using images from the colour base map imaging campaign during MESSENGER's primary mission. 

These colours are not what Mercury would look like to the human eye, but rather the colours enhance the chemical, mineralogical, and physical differences between the rocks that make up Mercury's surface.

Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Mobile app diagnoses malaria from a single drop of blood

The virtual ink had barely dried on our story about the Skin Scan app for diagnosing melanoma when we received word of another, equally compelling mobile diagnostic tool.

Focusing this time on the millions of people at risk from malaria in sub-Saharan Africa and other parts of the world, Lifelens is a project that has created a smartphone app to diagnose the insidious, mosquito-borne disease.

More than one million people die each year from Malaria, and roughly 85 percent of them are children under the age of 5, the Lifelens project notes. The most prevalent diagnostic tool, meanwhile, is the rapid diagnostic test (RDT), which is known to be associated with a 60 percent incidence rate of false positive results.

That, in turn, results in the treatment of many people who don’t actually have Malaria, driving up the costs of anti-Malaria treatment significantly. The Lifelens project, on the other hand, aims to make the process both cheaper and more accurate by analyzing blood digitally instead.

Specifically, once blood is stained to reveal the Malaria parasites, the project’s smartphone app can analyze a magnified image of a drop of blood captured via simple finger prick, including counting the various types of cells it includes. Malarial parasites are among those it can identify, making false results much less likely.

Once analysis is complete, data is uploaded to the Web, where it can be mapped for a high-level view of where Malaria outbreaks are occurring.

The video below demonstrates Lifelens in action:

NASA - microgravity flame images

Fire acts differently in space than on Earth. Sandra Olson, an aerospace engineer at NASA's Glenn Research Center, demonstrates just how differently in her art.

This artwork is comprised of multiple overlays of three separate microgravity flame images.

Each image is of flame spread over cellulose paper in a spacecraft ventilation flow in microgravity.

The different colours represent different chemical reactions within the flame. The blue areas are caused by chemiluminescence (light produced by a chemical reaction.) The white, yellow and orange regions are due to glowing soot within the flame zone.

Microgravity combustion research at Glenn not only provides insights into spacecraft fire safety, but it has also been used to create award-winning art images. This image won first place in the 2011 Combustion Art Competition, held at the 7th U.S. National Combustion Meeting.

Image Credit: NASA

Underwater Ordnance Watch: The search for discarded chemical agents outside Pearl Harbor

What Margo Edwards calls “My Scientific Detective Story” begins with flashbacks.

World War II is over. Mustard agent (a liquid used to produce mustard gas) has been stockpiled for decades from Europe to Asia.

Disposal options: bury, burn or dump the containers at sea.

Years later, Baltic Sea fishermen find unusual nodules in their nets. The polymerised balls contain liquid that burns the skin of people who come in contact with it.

The United States signs a 1975 treaty banning ocean disposal of chemical weapons. One year later, scientists conducting a biological survey for the Department of Defense south of Pearl Harbour find a dozen leaky cylinders; people handling them suffer mustard burns. A follow-up survey observes conventional munitions, but no additional mustard containers.

Further information at University of Hawaii website