astrobiology – Geobites

August 25, 2021August 25, 2021

Mysterious methane on Mars

Featuring image: northern rim of Gale Crater viewed by Curiosity. NASA/JPL-Caltech/MSSS, public domain (CC0)

Paper: Day-night differences in Mars methane suggest nighttime containment at Gale crater

Authors: C. R. Webster, P. R. Mahaffy, J. Pla-Garcia, S. C. R. Rafkin, J. E. Moores, S. K. Atreya, G. J. Flesch, C. A. Malespin, S. M. Teinturier, H. Kalucha, C. L. Smith, D. Viúdez-Moreiras and A. R. Vasavada

Methane is a gas often connected to life on Earth. NASA’s Mars rover reported the detection of methane, but discrepancies with other missions puzzled researchers. Is there methane on Mars or not? A new study tries to answer this question in a windy way.

Methane is a possible biosignature for extraterrestrial life and therefore, one of the goals of the Mars rover Curiosity was to search for methane. Curiosity was able to detect varying amounts of this gas over the years, but the existence of methane in the Martian atmosphere could not be confirmed by analysis from satellites. Now, Christopher Webster and his group were able to explain the variations as well as the discrepancy between ground-based and satellite analysis by developing a detailed model of the wind systems at Gale crater.

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August 19, 2021August 20, 2021

The Search for Life on Mars Begins on Earth

Self portrait of NASA's Curiosity rover. Curiosity is currently climbing Moount Sharp, which can be seen rising on the right-hand side of the image, seeking signs that Mars have been a habitable planet in the past.

Article: Fatty Acid Preservation in Modern and Relict Hot-Spring Deposits in Iceland, with Implications for Organics Detection on Mars

Authors: Williams, Amy J., Kathleen L. Craft, Maëva Millan, Sarah Stewart Johnson, Christine A. Knudson, Marisol Juarez Rivera, Amy C. McAdam, Dominique Tobler, and John Roma Skok.

The quest to find signs of life on Mars is one of the greatest scientific challenges of our time. For some researchers, the quest is a chemical one. A search for the biomolecular remains of life that may have lived when Mars was warmer and wetter billions of years ago. However, finding and recognizing molecular fossils is no easy task, even for a rover as sophisticated as Curiosity. Now, new research from Dr. Amy Williams and her colleagues provides fresh insights into where Mars rovers should look for these fossils, what the signatures may look like, and a simple procedure for how to detect them.

June 27, 2021June 27, 2021

The only way is… down? Groundwater on Mars could support microbial life in the present day

Featured image: A person exploring the rocks of a cave on Earth, Pixabay.

Paper: Earth-like Habitable Environments in the Subsurface of Mars

Authors: J.D. Tarnas, J.F. Mustard, B. Sherwood Lollar, V. Stamenković, K.M. Cannon, J.-P. Lorand, T.C. Onstott, J.R. Michalski, O. Warr.

Mars exploration has been looking “up” recently: the Ingenuity helicopter performed the first powered flight on another planet, and veteran rover Curiosity gave us stunning images from the top of Mount Mercou. But if we want to look for life on Mars, it might be time for us to look down instead. New research suggests that life on present day Mars could be sustained by chemical energy produced through the interaction between water and rocks deep underground, like it is here on Earth.

April 21, 2021April 21, 2021

Oxia Planum: ExoMars 2022 Landing Site

Featured Image: Artist’s impression of ESA’s ExoMars rover ‘Rosalind Franklin’ on the surface of Mars. Credit: ESA.

Paper: Oxia Planum: The Landing Site for the ExoMars “Rosalind Franklin” Rover Mission: Geological Context and Prelanding Interpretation

Authors: Quantin-Nataf et al., 2021

We are entering a new dawn of Mars exploration: Perseverance rover touched down on Mars earlier this year, which marks the start of what will be a decade-long effort to return samples from Mars. In 2022 the European Space Agency (ESA) will launch the ExoMars rover, which will team up with the ExoMars Trace Gas Orbiter (TGO) to find evidence of past or present life on Mars.

April 19, 2021April 20, 2021

Are we star dust?

Paper: Amino acid abundances and compositions in iron and stony‐iron meteorites

Authors: Jamie E. Elsila, Natasha M. Johnson, Daniel P. Glavin, José C. Aponte, Jason P. Dworkin

All known life on Earth relies on amino acids. Many important biomolecules like proteins are made up of them. Scientists were surprised when they found these molecules, which are so strongly connected to living systems, in meteorites. How amino acids form in non-biological systems is still not entirely understood and is closely tied to the question of how life emerged on our young planet.

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November 26, 2020November 26, 2020

It’s LeviOsa, Not LevioSA: The Science Of Levitating Mud On Mars

Featured image: A mud volcano and mud flows in Azerbaijan. Credit: CAS/ Petr Brož/ CC BY-SA 4.0.

Paper: Mud flow levitation on Mars: Insights from laboratory simulations

Authors: Petr Brož et al.,

The Mariner spacecraft’s first images of Mars in the 1960s and 70s showed large volcanoes and flow features, most likely lava or mud. These features were largely interpreted to be lava flows because they look similar to those seen on Earth. However, a 2020 study by Brož et al., shows that mud flows may be more prevalent on Mars than first hypothesized.

November 16, 2020November 17, 2020

New instrument maps and preserves frozen habitats on Earth- and potentially icy worlds

Featured Image: Iceberg in North Star Bay, Greenland by Jeremy Harbeck – NASA, Public Domain

Paper: Subsurface In Situ Detection of Microbes and Diverse
Organic Matter Hotspots in the Greenland Ice Sheet

Authors: Michael J. Malaska, Rohit Bhartia, Kenneth S. Manatt, John C. Priscu, William J. Abbey, Boleslaw Mellerowicz, Joseph Palmowski, Gale L. Paulsen, Kris Zacny, Evan J. Eshelman, and Juliana D’Andrilli

Like the rings of a tree, core samples extracted from glacial ice preserve a unique record of past events. But instead of recording seasonal growth, the ancient ice sheets of Antarctica and Greenland have preserved the conditions of long gone climates and ecosystems. Some sheets have continuously accumulated so much snowfall over the past series of millennia that in some places the ice can reach depths that are miles deep. Analyzing this immense glacial record can inform us about not just the global patterns of climate change, but also the evolution of microbial life on Earth, and maybe even the icy worlds of our Solar System.

October 15, 2020October 15, 2020

Water, but not a drop to drink: multiple salty lakes beneath the south pole of Mars?

Featured image: The south pole of Mars as seen by the HRSC Camera onboard the European Space Agency’s Mars Express mission. Image credit: ESA/DLR/FU Berlin.

Paper: Multiple subglacial water bodies below the south pole of Mars unveiled by new MARSIS data.

Authors: Sebastian Emanuel Lauro, Elena Pettinelli, Graziella Caprarelli, Luca Guallini, Angelo Pio Rossi, Elisabetta Mattei, Barbara Cosciotti, Andrea Cicchetti, Francesco Soldovieri, Marco Cartacci, Federico Di Paolo, Raffaella Noschese and Roberto Orosei.

“Water, water everywhere, but not a drop to drink”- or at least that might be the case beneath the south pole of Mars. In 2018, a team of scientists reported a potential subsurface lake of liquid water 1.5 km beneath the Martian south polar cap. Now, using more observations as well as new analysis methods previously used for ice sheets on Earth, the same team presents new evidence for a large subsurface lake as well as three other lakes in the same area. This raises further questions about how such lakes could be kept liquid in the cold environment of Mars, and whether they could provide a habitable environment for astrobiology.

August 20, 2020August 21, 2020

Lava tubes on the Moon and Mars might be big and stable enough for humans to live in

Featured image: A hole with approximately 150 metres diameter, indicating a potential lava tube on Mars. Public Domain (NASA/JPL/University of Arizona).

Paper: Lava tubes on Earth, Moon and Mars: A review on their size and morphology revealed by comparative planetology

Authors: Francesco Sauro, Riccardo Pozzobon, Matteo Massironi, Pierluigi De Berardinis, Tommaso Santagata, Jo De Waele.

Editor’s note: due to an editorial mixup, two Geobites authors—unbeknownst to each other—wrote about the same paper. We encourage readers to take advantage of this opportunity to learn how two different geoscientists would describe the same exciting development in their field. The other post is here.

When you picture living on another planet, you probably don’t imagine living underground. But lava tubes – underground cave systems formed by flowing lava – are more sheltered from radiation and micrometeorites than the surface of the Moon or Mars. They are also more stable in temperature and could contain water ice. For these reasons both popular culture, such as the National Geographic Mars series, and scientists alike, have hypothesised that humans might live in them one day. Now, a new review and analysis study led by Francesco Sauro at the University of Bologna has sought to investigate potential lava tubes on both the Moon and Mars.

July 29, 2020August 21, 2020

Looking for life on Mars: what can the valleys that once flowed into Jezero crater tell us about the best rocks to sample?

Featured image: Artist depiction of the Mars 2020 Perseverance Rover on Mars. Public domain (NASA/JPL-Caltech).

Paper: Fluvial Regimes, Morphometry, and Age of Jezero Crater Paleolake Inlet Valleys and Their Exobiological Significance for the 2020 Rover Mission Landing Site.

Authors: Nicolas Mangold, Gilles Dromart, Veronique Ansan, Francesco Salese, Maarten G. Kleinhans, Marion Masse, Cathy Quantin-Nataf, and Kathryn M. Stack.

On Mars, we see a very different landscape to that on Earth. Although now an arid planet, great scars visible from space – such as the colossal Valles Marineris, which dwarfs Earth’s Grand Canyon – hint at a once watery world. But scientists still aren’t sure whether water on Mars might once have hosted life. On the 30^th of July, NASA will launch the Mars 2020 mission, which will gather clues about the planet’s past and seek signs of ancient life on Mars. An essential part of such a space mission is extensive planning, so that scientists can target the most important rocks for study and sampling when the rover gets to Mars. A recent study by Nicolas Mangold and colleagues did just that by looking closely at the landing site for this next Mars mission, known as Jezero crater.