Published 2023
| Version v1
Journal article
Chasing rainbows and ocean glints: Inner working angle constraints for the Habitable Worlds Observatory
Creators
- Vaughan, Sophia R.
- Gebhard, Timothy D.
- Bott, Kimberly
- Casewell, Sarah L.
- Cowan, Nicolas B.
- Doelman, David S.
- Kenworthy, Matthew
- Mazoyer, Johan
- Millar-Blanchaer, Maxwell A.
- Trees, Victor J. H.
- Stam, Daphne M.
- Absil, Olivier
- Altinier, Lisa
- Baudoz, Pierre
- Belikov, Ruslan
- Bidot, Alexis
- Birkby, Jayne L.
- Bonse, Markus J.
- Brandl, Bernhard
- Carlotti, Alexis
- Choquet, Elodie
- van Dam, Dirk
- Desai, Niyati
- Fogarty, Kevin
- Fowler, J.
- van Gorkom, Kyle
- Gutierrez, Yann
- Guyon, Olivier
- Haffert, Sebastiaan Y.
- Herscovici-Schiller, Olivier
- Hours, Adrien
- Juanola-Parramon, Roser
- Kleisioti, Evangelia
- König, Lorenzo
- van Kooten, Maaike
- Krasteva, Mariya
- Laginja, Iva
- Landman, Rico
- Leboulleux, Lucie
- Mouillet, David
- N'Diaye, Mamadou
- Por, Emiel H.
- Pueyo, Laurent
- Snik, Frans
Contributors
Others:
- Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA) ; Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
- Laboratoire d'Astrophysique de Marseille (LAM) ; Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
- Institut de Planétologie et d'Astrophysique de Grenoble (IPAG) ; Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France
- Université Paris Cité (UPCité)
- Observatoire de la Côte d'Azur (OCA) ; Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Description
NASA is engaged in planning for a Habitable Worlds Observatory (HabWorlds ), a coronagraphic space mission to detect rocky planets in habitable zones and establish their habitability. Surface liquid water is central to the definition of planetary habitability. Photometric and polarimetric phase curves of starlight reflected by an exoplanet can reveal ocean glint, rainbows, and other phenomena caused by scattering by clouds or atmospheric gas. Direct imaging missions are optimized for planets near quadrature, but HabWorlds ' coronagraph may obscure the phase angles where such optical features are strongest. The range of accessible phase angles for a given exoplanet will depend on the planet's orbital inclination and/or the coronagraph's inner working angle (IWA). We use a recently created catalog relevant to HabWorlds of 164 stars to estimate the number of exo-Earths that could be searched for ocean glint, rainbows, and polarization effects due to Rayleigh scattering. We find that the polarimetric Rayleigh scattering peak is accessible in most of the exo-Earth planetary systems. The rainbow due to water clouds at phase angles of ~20○ - 60○ would be accessible with HabWorlds for a planet with an Earth equivalent instellation in ~46 systems, while the ocean glint signature at phase angles of ~130○ - 170○ would be accessible in ~16 systems, assuming an IWA = 62 mas (3λ/D). Improving the IWA = 41 mas (2λ/D) increases accessibility to rainbows and glints by factors of approximately 2 and 3, respectively. By observing these scattering features, HabWorlds could detect a surface ocean and water cycle, key indicators of habitability.
Abstract
International audienceAdditional details
Identifiers
- URL
- https://insu.hal.science/insu-04505555
- URN
- urn:oai:HAL:insu-04505555v1
Origin repository
- Origin repository
- UNICA