Eleni Ravanis – Geobites

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.

December 23, 2020December 23, 2020

How did valleys form on early Mars? Some say in ice…

Featured image: The Nirgal Vallis river valley on Mars as seen by the HRSC Camera onboard the European Space Agency’s Mars Express mission. Image credit: ESA/DLR/FU Berlin.

Paper: Valley formation on early Mars by subglacial and fluvial erosion.

Authors: Anna Grau Galofre, A. Mark Jellinek & Gordon R. Osinski.

“Some say the world will end in fire/ Some say in ice” begins the famous poem by Robert Frost. But what about how worlds begin? For years the theory of a “warm and wet” early Mars has been the conventional explanation for the vast valley networks formed billions of years ago that we can see on the surface today. Now, a new study suggests that at least some of these valleys could have formed under colossal ice sheets, in a distinctly more icy world.

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.