Rovers on Mars should be looking for rocks that look like pasta – they're almost certainly created by life

According to a new NASA-funded study that appeared in AstrobiologyThe next missions to Mars should be on the lookout for rocks that look like "fettuccine". The reason for this, according to the research team, is that the formation of these types of rocks is controlled by a form of ancient and hardy bacteria.

This bacteria is known as Sulfurihydrogenibium yellowstonense, which belongs to a lineage that evolved over 2.35 billion years ago, a time that coincides with the earlier portion of the Great Oxygenation Event. Using sulfur dioxide and carbon dioxide as energy sources, this is one of the most important sources of heat.

In hot springs, the microbe assembles itself into strands and promotes the crystallization of calcium carbonate rock (aka. Travertine), which is what gives it its "pasta-like" appearance. This behavior makes it relatively easy to detect when conducting surveys and would make it easy to identify when looking for signs of life on other planets.

Bruce Fouke, a professor of geology and an affiliate professor at the Carl R. Woese Institute for Genomic Biology (IGB) at the University of Illinois, was also the lead researcher on the study. "It has an unusual name, Sulfurihydrogenibium yellowstonense, "He said in an interview with the Illinois News Bureau. "We just call it 'Sulfuri … Taken together, these traits make it a prime candidate for colonizing Mars and other planets."

The unique-shape and structure of these strands are the result of this environment. Given that they inhabit fast-flowing water, the Sulfuri bacteria form in chains in order to prevent from being washed away. This way, they are able to remain attached to rock formations and absorb nutrients from the hot springs. As Fouke explained:

"They form tightly wound cables that a wave is fixed on one end. The waving cables keep other microbes from attaching. Sulfuri also defends itself by oozing a slippery mucus. These Sulfuri cables look amazingly like pasta fettuccine, while further downstream they look more like capellini pasta. "

To analyze the bacteria, the researchers collecting samples from Mammoth Hot Springs in Yellowstone National Park, using sterilized pasta forks (of all things!) The team then studies the microbial genomes to evaluate which genes have been actively transplanted into proteins, which allowed them to discern the organism's metabolic needs.

The team also examined the bacterial properties of calcium carbonate and crystallized calcium carbonate in the field of calcium carbonate. In fact, they determine that these proteins cause crystallization at a rate that is one billion times greater than that of a planet.

As Fouke pointed out, this type of bacteria and the resulting rock formations are something that should be discernible for biosignature:

"This should be an easy form of fossilized life for a rover to detect on other planets. If we see the deposition of this kind of extensive filamentous rock on other planets, we would know it's a fingerprint of life. It's big and it's unique. No other rocks look like this. It would be definitive evidence of the presences of alien microbes. "

A little over a year from now, NASA's March 2020 rover will be heading to the Red Planet to carry on in the hunt for life. One of the rover's main objectives will be collected and left in the future. If the rover does come across those formations where hot springs have been thought to exist, it is entirely possible that they will contain the fossilized remains of bacteria.

Needless to say, a sample of that would be invaluable, as it would prove that Earth is not unique in having brought forth life. Be sure to check out this video of the team's field research in Yellowstone National Park, courtesy of the Institute for Genomic Biology (IGB) Illinois:

Further Reading: Illinois News Bureau, Astrobiology