PLANET-HAB COLLABORATION

The Planet-Hab Collaboration is a global consortium of scientists dedicated to advancing and applying habitability models within the field of astrobiology. This collective's scientific strategy employs innovative modeling techniques to analyze and assess the potential for life across a diverse array of environments, including terrestrial, planetary, and exoplanetary settings.

Recent advancements in astrobiology, such as the application of Habitat Suitability Models (HSM), open the possibility of detailed and formal studies of planetary habitability or astroecology (Méndez et al., 2021; Meurer et al., 2024). Habitability in astrobiology usually focuses on determining whether planets are habitable, a binary problem that is hard to quantify (Cockell et al., 2022). In fact, the only way to answer this problem is by finding life, which requires the detection of biosignatures. In contrast, habitability in ecology is about determining how suitable for life are a set of environmental variables, a continuous and quantifiable problem.

The Astro2020 decadal survey explicitly identifies the need for a "comprehensive multifactorial framework for habitability assessment” as part of the necessary interdisciplinary theory to answer the science question "E-Q3: How do habitable environments arise and evolve within the context of their planetary systems?” of the “Discovery Area: The Search for Life on Exoplanets.”

Press Release: Breaking Old Habits: New Models for Habitability Beyond Earth

Models for Exoplanets

The habitable zone (HZ) has long been an astronomical standard in the search for extraterrestrial life, serving as the zeroth-order approximation for identifying potentially habitable worlds. While practical, this approximation primarily focuses on the distance of a planet from its star, assuming that distance is one key determinant for liquid water stability. New telescopes, such as the JWST and the future Habitable Worlds Observatory (HWO), would start characterizing the atmosphere and then the surfaces of nearby exoplanets. These observations would need to be weighted in terms of their habitability and biosignature potential compared to Earth's past and present. If the HZ is the zeroth-order approximation, what is the first-order approximation to planetary habitability?

References

Cockell C. S., Samuels T., Stevens A. H. (2022) Habitability Is Binary, But It Is Used by Astrobiologists to Encompass Continuous Ecological Questions. Astrobiology. 22(1):7-13. DOI: 10.1089/ast.2021.0038.

Méndez, A. Commentary: How to determine the right conditions for alien life. (2022) Physics Today, (15 Jun 2022), 1945-0699. DOI: 10.1063/PT.6.3.20220615a.

Méndez, A., Rivera-Valentín, E. G., Schulze-Makuch, D., Filiberto, J., Ramírez, R. M., Wood, T. E., Dávila, A., McKay, C., Ortiz Ceballos, K. N., Jusino-Maldonado, M., Torres-Santiago, N. J., Nery, G., Heller, R., Byrne, P. K., Malaska, M. J., Nathan, E., Simões, M. F., Antunes, A., Martínez-Frías, J., Carone, L., Izenberg, N. R., Atri, D., Carvajal Chitty, H. I., Nowajewski-Barra, P., Rivera-Hernández, F., Brown, C., Lynch, K., Catling, D., Zuluaga, J. I., Salazar, J. F., Chen, H., González, G., Kashyap Jagadeesh, M., Haqq-Misra, J. (2021). Habitability Models for Astrobiology. Astrobiology, 21(8), 1017-1027. DOI: 10.1089/ast.2020.2342. (arxiv.org/abs/2108.05417)

Méndez, A., Rivera-Valentín, E. G., Schulze-Makuch, D., Filiberto, J., Ramírez, R. M., Wood, T. E., Dávila, A., McKay, C., Ortiz Ceballos, K. N., Jusino-Maldonado, M., Torres-Santiago, N. J., Nery, G., Heller, R., Byrne, P. K., Malaska, M. J., Nathan, E., Simões, M. F., Antunes, A., Martínez-Frías, J., Carone, L., Izenberg, N. R., Atri, D., Carvajal Chitty, H. I., Nowajewski-Barra, P., Rivera-Hernández, F., Brown, C., Lynch, K., Catling, D., Zuluaga, J. I., Salazar, J. F., Chen, H., González, G., Kashyap Jagadeesh, M., Haqq-Misra, J., Barnes, R. ; Cockell, C. S. (2021). Planetary Science and Astrobiology Decadal Survey 2023-2032 white paper e-id. 065; Bulletin of the American Astronomical Society, Vol. 53, Issue 4, e-id. 065. DOI: 10.3847/25c2cfeb.20609a88. (arxiv.org/abs/2007.05491)

Meurer, J. C., Haqq-Misra, J., Mendonça, M. de S. (2024) Astroecology: bridging the gap between ecology and astrobiology. International Journal of Astrobiology, 23:e3. DOI: 10.1017/S1473550423000265

Rivera-Valentín, E. G., Méndez, A., Lynch, K., Soto, A. (2024) Habitat Suitability Index Models for Mars. PSJ, in review.

Contact

Prof. Abel Méndez, PHL @ UPR Arecibo: abel.mendez@upr.edu

Dr. Edgard G. Rivera-Valentín, JHUAPL, rivera-valentin@lpi.usra.edu

Dr. Dirk Schulze-Makuch, Technische Universität Berlin, schulze-makuch@tu-berlin.de