Rock of Mars is a rare and precious resource here on earth. So far, the only monsters we have are pieces of meteorite that are removed from the red planet and move through the solar system until they hit the earth.
A small piece of this valuable stuff has just been used fascinatingly: scientists make up a small piece of the Martian Black Beauty meteorite and use it to cultivate extremophilic microbes.
Not only does it show that life can exist in real Mars conditions, but it offers astrobiologists new biosignatures that they can use to look for signs of ancient life in the crust of Mars.
“Black beauty is one of the rarest substances on earth, it is a unique Marsbreccia formed by different pieces of Mars crust (some of which are dated to 4.42 ± 0.07 billion years) and have emitted millions [of] years ago from the surface of Mars, ‘said astrobiologist Tetyana Milojevic of the University of Vienna in Austria.
“We had to take a fairly daring approach to smashing a few grams of precious Mars Rocks to recreate the possible appearance of Mars’ earliest and simplest life form.”
If there was ancient life on Mars, it most likely looks like an extremophile. These are organisms that live in conditions that we once considered too hostile to sustain life, such as sub-zero, super-salt lakes in Antarctica, or volcanic geothermal springs, or the lower crust of the earth, deep beneath the seabed.
On ancient Mars, billions of years ago, we are pretty sure that the atmosphere was thick and rich in carbon dioxide. We have a sample of the rock that makes up the Mars crust, when the planet was just a baby.
Here on Earth, organisms that can dissolve carbon dioxide and convert inorganic compounds (such as minerals) into energy are known as chemolitotrophs, and therefore the research team is investigating the type of organism that may have lived on Mars.
“We can assume that life forms similar to chemolithotrophs existed there in the early years of the red planet,” Milojevic said.
The microbes they chose were Metallosphaera sedula, a thermosidophilic Argyrates found in hot, acidic volcanic fountains. It was placed on the Mars mineral in a bioreactor that was carefully heated and gasified with air and carbon dioxide. The team used microscopy to observe the growth of cells.
It has indeed grown – and the background of Black Beauty, which has been left behind, has enabled scientists to see how the microbes used and transformed the material to build cells and leave biomineral deposits. They used the transmission electron microscopy to study these deposits up to the atomic scale.
“Grown on material from the Mars crust, the microbes form a robust mineral capsule [sic] of complex iron, manganese and aluminum phosphates, ”said Milojevic.
“Apart from the massive incubation of the cell surface, we observed intracellular formation of crystal deposits of a very complex nature (Fe, Mn oxides, mixed Mn silicates). These are characteristic unique features of growth on the Noachian Martian breccia, which we have not previously observed when these microbes were grown on terrestrial mineral resources and a rocky chondritic meteorite. ‘
It can provide invaluable value in the search for ancient life on Mars. The Perseverance Rover, which arrived on the red planet last week, will specifically look for such bioteches. Now astrobiologists know what the M. sedula crystal deposits, it may be easier to identify similar things in Percy’s monsters.
The researchers also emphasize the importance of using real Mars samples to conduct such studies. Although we have simulated available Mars regoliths, and Mars meteorites are scarce, we can get invaluable by using the right thing.
Part of Perseverance’s mission is to collect samples of Mars rock that will hopefully be returned to Earth within the next decade. Scientists will surely shout for the substance, but we have no doubt that some will be earmarked for extremophile research.
“Astrobiology research on Black Beauty and other similar ‘Flowers of the Universe’ can provide valuable knowledge for the analysis of returned Mars samples to determine their potential biogenicity,” Milojevic said.
The research was published in Communication Earth and environment.