Astrobiology — NExSS ROCKE3D Project
For a full list of publications related to ROCKE-3D, please see the SAO/NASA Astrophysics Data System (ADS) library. The following lists those publications with NASA/GISS authors.
The inner Solar System's habitability through time: Earth, Mars, and Venus, irradiated by an evolving Sun, have had fascinating but diverging histories of habitability. Although only Earth’s surface is considered to be habitable today, all three planets might have simultaneously been habitable early in their histories. We consider how physical processes that have operated similarly or differently on these planets determined the creation and evolution of their atmospheres and surfaces over time.
Del Genio, A.D., D. Brain, L. Noack, and L. Schaefer, 2018: The inner Solar System's habitability through time, submitted for inclusion in Planetary Astrobiology, University of Arizona Press.
Possible climates of Proxima Centauri b: The first exoplanet discovered orbiting the nearest star to Earth, Proxima Centauri, may be small enough to be a rocky planet and at a distance from its star that gives it a chance to be habitable. To inform future observations, we simulated possible climates of Proxima Centauri b with ROCKE-3D. We find that the presence of a dynamic ocean that moves excess heat to colder regions permits a wide range of climates with an least some liquid water on the surface, even on the nightside of planets that are never illuminated by the star.
• Del Genio, A.D., M.J. Way, D.S. Amundsen, I. Aleinov, M. Kelley, N.Y. Kiang, and T.L. Clune, 2018: Habitable climate scenarios for Proxima Centauri b with a dynamic ocean. Astrobiology, early on-line.
Exoplanet biosignatures: The rapid rate of discoveries of exoplanets has expanded the scope of the science possible for the remote detection of life beyond Earth. A NExSS workshop engaged the international scientific community across diverse scientific disciplines, to assess the state of the science and technology in the search for life on exoplanets, and to identify paths for progress. The workshop produced and introduction and five review papers that provide: 1) a review of known and proposed biosignatures; 2) an in-depth review of O2 as a biosignature, rigorously examining false positives and negatives for evidence of life; 3) a Bayesian framework to organize current understanding to quantify confidence in biosignature assessments; 4) an extension of that framework in anticipation of increasing planetary data and novel concepts of biosignatures, and 5) a review of the upcoming telescope capabilities to characterize exoplanets and their environments.
• Kiang, N.Y., S. Domagal-Goldman, M.N. Parenteau, D.C. Catling, Y. Fujii, V.S. Meadows, E.W. Schwieterman, and S.I. Walker, 2018: Exoplanet biosignatures: At the dawn of a new era of planetary observations. Astrobiology, 18, 619-629, doi:10.1089/ast.2018.1862.
• Schwieterman, W., N.Y. Kiang, M.N. Parenteau, C.E. Harman, S. DasSarma, T.M. Fisher, G.N. Arney, H.E. Hartnett, C.T. Reinhard, S.L. Olson, V.S. Meadows, C.S. Cockell, S.I. Walker, J.L. Grenfell, S. Hegde, S. Rugheimer, R. Hu, and T.W. Lyons, 2018: Exoplanet biosignatures: A review of remotely detectable signs of life. Astrobiology, 18, no. 6, 663-708, doi:10.1089/ast.2017.1729.
• Catling, D.C., J. Krissansen-Totton, N.Y. Kiang, D. Crisp, T.D. Robinson, S. DasSarma, A. Rushby, A.D. Del Genio, W. Bains, and S. Domagal-Goldman, 2018: Exoplanet biosignatures: A framework for their assessment. Astrobiology, 19, no. 6, 709-738, doi:10.1089/ast.2017.1737.
• Fujii, Y., D. Angerhausen, R. Deitrick, S. Domagal-Goldman, J.L. Grenfell, Y. Hori, S.R. Kane, E. Palle, H. Rauer, N. Siegler, K. Stapelfeldt, and K.B. Stevenson, 2018: Exoplanet biosignatures: Observational prospects. Astrobiology, 18, no. 6, 739-778, doi:10.1089/ast.2017.1733.
• Walker, S.I., W. Bains, L. Cronin, S. DasSarma, S. Danielache, S. Domagal-Goldman, B. Kacar, N.Y. Kiang, A. Lenardic, C.T. Reinhard, W. Moore, E.W. Schwieterman, E.L. Shkolnik, and H.B. Smith, 2018: Exoplanet biosignatures: Future directions. Astrobiology, 18, no. 6, 779-824.
Re-thinking the moist greenhouse limit for the inner edge of the habitable zone: The traditional view of the inner edge of the habitable zone has been that once a planet receives a stellar flux slightly greater than Earth does, convective storms inject large amounts of water vapor into the stratosphere, eventually leading to loss of the oceans. ROCKE-3D simulations show that this transition is caused by a circulation driven by stellar heating rather than by convection and is gradual rather than sudden, implying that planets can remain habitable much closer to their stars than previously thought. Read the NASA News Feature.
• Fujii, Y., A.D. Del Genio, and D.S. Amundsen, 2017: NIR-driven moist upper atmospheres of synchronously rotating temperate terrestrial exoplanets. Astrophys. J., 848, no. 2, 100, doi:10.3847/1538-4357/aa8955.
Release of the first version of ROCKE-3D: The first generation of the ROCKE-3D GCM, called Planet_1.0, has been created and is being used for current research projects. The code is available at the Simplex software repository, and a paper describing the model has been published.
• Way, M.J., I. Aleinov, D.S. Amundsen, M.A. Chandler, T. Clune, A.D. Del Genio, Y. Fujii, M. Kelley, N.Y. Kiang, L. Sohl, and K. Tsigaridis, 2017: Resolving Orbital and Climate Keys of Earth and Extraterrestrial Environments with Dynamics 1.0: A general circulation model for simulating the climates of rocky planets. Astrophys. J. Supp. Series, 231, no. 1, 12, doi:10.3847/1538-4365/aa7a06.
Climate effects of the evolution of eccentricity of an Earthlike planet due to a nearby giant planet: An orbital evolution model was used to predict long-term changes in the orbital eccentricity of a neighboring Earthlike planet, and ROCKE-3D was used to predict the resulting swings in climate over almost 7000 years. The presence of a dynamic ocean that stores heat and transports it from warm to cold places keeps the climate stable despite the large variations in incident sunlight between periapsis and apoapsis.
• Georgakarakos, N., I. Dobbs-Dixon, and M.J. Way, 2016: Long term evolution of planetary systems with a terrestrial planet and a giant planet. Mon. Not. Roy. Astron. Soc., 461, no. 2, 1512-1528, doi:10.1093/mnras/stw1378.
• Way, M.J., and N. Georgakarakos, 2017: Effects of variable eccentricity on the climate of an Earth-like world. Astrophys. J. Lett., 835, no. 1, L1, doi:10.3847/2041-8213/835/1/L1.
Ancient Venus may have been habitable for several billion years: ROCKE-3D simulations assuming an early Venus shallow ocean consistent with the observed D/H ratio and a land-ocean pattern determined by Magellan topography data suggest that if Venus cooled down after its formation and retained some of its initial water inventory, its climate may have become stable and remained that way between 2.9 and 0.7 Gya due to the reflective convectively generated clouds that can shield the dayside of a planet if it rotates slowly enough. Read the NASA news feature.
• Way, M.J., A.D. Del Genio, N.Y. Kiang, L.E. Sohl, D.H. Grinspoon, I. Aleinov, M. Kelley, and T. Clune, 2016: Was Venus the first habitable world of our solar system? Geophys. Res. Lett., 43, no. 16, 8376-8383, doi:10.1002/2016GL069790.