Article
Astronomy & Astrophysics
Laura M. Barge, Laura E. Rodriguez, Jessica M. Weber, Bethany P. Theiling
Summary: The field of prebiotic chemistry studies the complex organic chemical systems that exhibit life-like properties, which can be produced abiotically in the laboratory. Understanding and interpreting organic signatures detected during planetary missions are crucial in astrobiology and life detection research, and involve gaining a deeper understanding of prebiotic/abiotic chemical possibilities in diverse planetary environments. Additionally, utilizing experimental prebiotic samples as analogues when generating comparison libraries for life-detection mission instruments is recommended.
Article
Biochemistry & Molecular Biology
Harrison B. Smith, Cole Mathis
Summary: Astrobiology aims to determine the distribution and diversity of life in the universe, but the problem of determining if exoplanets contain life without a theory of life poses an existential question. Focusing on unambiguous features of life in four areas is advocated to resolve this problem.
Article
Multidisciplinary Sciences
R. J. Anslow, A. Bonsor, P. B. Rimmer
Summary: This work explores the potential of cometary impacts to deliver complex organic molecules and prebiotic building blocks to rocky exoplanets. It shows that impacts at very low velocities are required for the survival of these molecules. The study finds that comets scattered from beyond the snow-line into the habitable zone have a lower minimum impact velocity for planets orbiting Solar-type stars compared to M-dwarfs. The research suggests that the intact delivery of complex organic molecules is more likely in tightly packed planetary systems around high-mass stars. However, impacts onto planets around low-mass stars are sensitive to the planetary architecture and may not support the survival of complex prebiotic molecules. Rocky planets around M-dwarfs also face more high velocity impacts, which could pose challenges for life on these planets. In conclusion, the study predicts that the presence of biosignatures will be correlated with decreasing planetary mass, increasing stellar mass, and decreasing planetary separation.
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Review
Astronomy & Astrophysics
Robin Wordsworth, Laura Kreidberg
Summary: Rocky planets around other stars are common, but their atmospheric properties are still uncertain. Recent planet discoveries and upcoming advances in observing capability will allow us to characterize the atmospheres of many rocky exoplanets in this decade. Theoretical understanding of rocky exoplanet atmospheres has advanced considerably, providing testable predictions of their evolution, chemistry, dynamics, and possible biosignatures.
ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS
(2022)
Article
Multidisciplinary Sciences
Stuart M. Marshall, Cole Mathis, Emma Carrick, Graham Keenan, Geoffrey J. T. Cooper, Heather Graham, Matthew Craven, Piotr S. Gromski, Douglas G. Moore, Sara Walker, Leroy Cronin
Summary: The search for alien life is challenging due to uncertainties in defining signatures of living systems. Using the molecular assembly index and tandem mass spectrometry, this study presents a method for identifying molecules produced by biological systems and detecting biosignatures from various samples, including those from outer space.
NATURE COMMUNICATIONS
(2021)
Article
Biology
Nicholas Guttenberg, Huan Chen, Tomohiro Mochizuki, H. James Cleaves
Summary: The search for extraterrestrial life in the Solar System relies on distinguishing biological features from background signals using techniques like mass spectrometry. This method can effectively differentiate organic compounds produced by biological and abiological processes. It presents a general approach for detecting evidence of biology independently of the specific molecular makeup of samples, and may have implications for studying emergent living phenomena and paleobiological samples.
Article
Astronomy & Astrophysics
Zhuchang Zhan, Sara Seager, Janusz Jurand Petkowski, Clara Sousa-Silva, Sukrit Ranjan, Jingcheng Huang, William Bains
Summary: The search for possible biosignature gases in habitable exoplanet atmospheres is accelerating, with isoprene being added to the roster of potential biosignature gases. Despite challenges, isoprene is worth considering for its potential in detecting extraterrestrial life.
Article
Chemistry, Multidisciplinary
Ruvan de Graaf, Yannick De Decker, Victor Sojo, Reuben Hudson
Summary: The ongoing research on the emergence of life focuses on constructing hypothetical environments to produce organic molecules. Mineral catalysts are used in experiments to facilitate the supply of organics that may have produced prebiotic building blocks. However, most studies lack rigorous materials analyses and sub-stoichiometric amounts of metals or minerals, which are necessary to demonstrate the viability of catalysis. Future work should aim to decrease catalyst loading, increase productivity, and conduct rigorous materials analyses to provide evidence of true catalysis.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Multidisciplinary Sciences
Carina Lee, Jessica M. Weber, Laura E. Rodriguez, Rachel Y. Sheppard, Laura M. Barge, Eve L. Berger, Aaron S. Burton
Summary: Chirality plays a central role in the evolution of biological systems, but why biology has a strong preference for specific chiralities remains controversial. The chirality of organic compounds and minerals affects the preservation and detection of organic molecules. This paper reviews the properties and processes involved, and discusses laboratory reactions and analytical techniques, as well as current and future technologies in planetary missions.
Article
Astronomy & Astrophysics
Rhys Seeburger, Peter M. Higgins, Niall P. Whiteford, Charles S. Cockell
Summary: The viability of detecting methane produced by microbial activity in low-temperature hydrothermal vents on an Archean-Earth-like exoplanet in the habitable zone was explored using a simplified bottom-up approach with a toy model. Simulations of methanogens at hydrothermal vent sites in the deep ocean were used to determine biological methane production rates. These production rates were then used to estimate likely methane concentrations in the simplified atmosphere.
Article
Astronomy & Astrophysics
Caroline Dorn, Tim Lichtenberg
Summary: The deep volatile storage capacity of magma oceans has significant implications for exoplanet mass and radius data. Experimental petrology provides fundamental properties of water and melt mixing ability. An advanced interior model for water-rich rocky exoplanets has been introduced to test the effects of rock melting and water partitioning on planet radii. Models with and without these processes can lead to deviations in planet radius up to 16%, indicating potential underestimation of planetary bulk water content.
ASTROPHYSICAL JOURNAL LETTERS
(2021)
Article
Geochemistry & Geophysics
Paul B. Rimmer, Sukrit Ranjan, Sarah Rugheimer
Summary: The study of the origin of life on Earth and the search for life on other planets are closely linked. Laboratory research guides exploration within our Solar System and informs future exoplanet observations. Exoplanet research provides statistical context to conclusions about the nature and origins of life.
Article
Biology
Dominic Papineau, Kevin Devine, Bernardo Albuquerque Nogueira
Summary: The origin of life may have involved abiotic carbon redox reactions that produced lifelike patterns through chemically oscillating reactions (COR). COR are spontaneous, out-of-equilibrium, and redox reactions that decarboxylate carboxylic acids to produce CO2 and self-similar patterns. These patterns have circular concentricity, radial geometries, colour gradients, cavity structures, and branching, which are also observed in some eukaryotic lifeforms. Future research should investigate the role of halogens in biochemistry, COR in life-forms including humans, and the COR-stage of prebiotic carbon cycling on other planets like Mars.
Article
Geochemistry & Geophysics
Alan P. Jackson, Steven J. Desch
Summary: The study proposes that the interstellar object 1I/'Oumuamua may be composed of N-2 ice, with a high albedo, and was ejected from a young stellar system, potentially probing the surface compositions of a new type of exoplanet.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Review
Astronomy & Astrophysics
Abel Mendez, Edgard G. Rivera-Valentin, Dirk Schulze-Makuch, Justin Filiberto, Ramses M. Ramirez, Tana E. Wood, Alfonso Davila, Chris McKay, Kevin N. Ortiz Ceballos, Marcos Jusino-Maldonado, Nicole J. Torres-Santiago, Guillermo Nery, Rene Heller, Paul K. Byrne, Michael J. Malaska, Erica Nathan, Marta Filipa Simoes, Andre Antunes, Jesus Martinez-Frias, Ludmila Carone, Noam R. Izenberg, Dimitra Atri, Humberto Itic Carvajal Chitty, Priscilla Nowajewski-Barra, Frances Rivera-Hernandez, Corine Y. Brown, Kennda L. Lynch, David Catling, Jorge I. Zuluaga, Juan F. Salazar, Howard Chen, Grizelle Gonzalez, Madhu Kashyap Jagadeesh, Jacob Haqq-Misra
Summary: Habitability is defined as the capability of an environment to support life, with ecologists and astrobiologists using different models to study and propose different perspectives, which need to be integrated into new habitability standards.