Given that bacteria are literally everywhere - and I mean, everywhere - you wouldn't think that you would ever run out or find yourself needing to "hunt" them down.

Yet NASA is doing just that. It's not just hunting any old bacterial strains, though. NASA scientists are attempting to find strains on Mars.

The Planetary Science and Technology through Analog Research (PSTAR) Program's Atacama Rover Astrobiology Drilling Studies (ARADS) is a brand-new Mars rover analog mission, dedicated to finding signs of life underneath the soil of the red planet. Why underneath the soil, in particular? Scientists believe that due to the extreme radiation that scorches the surface of Mars, forms of life might have retreated underground. Thus the scientists working on the project have developed a slew of tools so far, ranging from a drill, a sample transfer arm, a Signs of Life Detector (SOLID), and the Wet Chemistry Lab (WCL), to probe underneath the soil (Hrala). These tools will ultimately be combined into one robot that will roam the Martian surface. Using these technologies, they hope to investigate what lives underneath Martian soil - if anything does at all.

Brian Glass, who is currently spearheading the NASA project, said, "Having both subsurface reach and surface mobility should greatly increase the number of biomarker and life-target sites we can sample."

Right now, investigators are testing these prototypes in the Atacama desert in Chile, which is allegedly the driest non-polar desert on Earth. Due to its track record of being extremely arid and hot for the past 10-15 million years, its environment is the closest thing on Earth that resembles Mars.

"Putting life-detection instruments in a difficult, Mars-analogue environment will help us figure out the best ways of looking for past or current life on Mars, if it existed," Glass added.

References

Hrala, J. NASA's testing its new "life-detection drill" in the Atacama Desert. Science Alert (2016).

Proposal Awarded for Atacama Rover Astrobiology Drilling Studies. NASA (2015).

Waller, D. Atacama Rover Astrobiology Drilling Studies - Night Falls. NASA (2015).

Photo Credits

The Planet Mars (NASA, ESA, and the Hubble Heritage Team via Wikimedia)

Valley in Atacama (via Wikimedia)

The answer is, of course: lots and lots of bacteria.

Imagine the amount of bacteria that paper money must carry. Paper money is something we don't wash, but that transfers hands almost incessantly. Imagine this scenario: You go to the grocery store and hand a $10 bill to the cashier for the fruit you buy. The cashier puts it into the box at her station. An hour later, a different employee comes and takes over the station. A different customer needs change, and the new cashier draws out your $10 bill and hands it to him or her. In just an hour, that single $10 bill has interacted with billions of bacteria from the hands of four different people. Now multiply that scenario by the millions of dollar bills circulating and the millions of human people that live on this planet (and not to mention the billions of bacterial cells on each person's hand), and soon you'll be wondering why on earth people don't wash their hands after handling paper money.

Paper money is constantly home to a variety of thriving microorganisms. To investigate what exactly types of microorganisms were found on dollar bills, scientists at the Center for Genomics and Systems Biology in New York analyzed a couple of them themselves from a bank in Manhattan. They found nearly 3,000 types of microorganisms, from various parts of the body - the skin, the mouth, and even the stomach.

The lead scientist of the study, Jane Carlton, the director of genome sequencing at the Center for Genomics and Systems Biology said, "Microbes are so important, are very ubiquitous and they surround us all the time." However, "[w]e did find certain microbes that we might be a little concerned about..."

These microbes constituted a variety of strains. Some were just associated with mild conditions like acne, but others were a lot more deadly. For instance, the scientists found Staphylococcus aureus (shown on the right), also called MRSA, on some bills. According to the MDH (Minnesota Department of Health), MRSA can cause "skin and soft tissue infections such as abscesses (boils), furuncles, and cellulitis." It's definitely not a bacteria I want to be in contact with! Some bills even revealed bacteria that could cause pneumonia (these pneumonia-causing bacteria, incidentally, were more commonly found on bills in the wintertime compared to the summertime). The ease and facility with which the scientists extracted these strains make them believe that these bills could be used as a mode of transmission.

A writer for the Wall Street Journal, Robert Hotz, wrote, "This unpublished research offers a glimpse into the international problem of dirty money...From rupees to euros, paper money is one of the most frequently passed items in the world. Hygienists have long worried that it could become a source of contagion."

Indeed, paper money could definitely transmit everyday diseases - and has the potential to even impact global health. I'll definitely be washing my hands after the next time I reach into my wallet!

References

Causes and Symptoms of Staphylococcus aureus. Minnesota Department of Health (2010).

Gonzalez, Elizabeth. Surprising Bacteria that Live on Your Money. ABC news (2014).

Paper Money Carries Thousands of Types of Bacteria. WebMD (2014).

Staphylococcal infections. MedlinePlus (2016).

Photo Credits

Banknotes with a face value of 5000 of different currencies (via Wikimedia Commons)

Staphylococcus aureus (via Wikimedia Commons)