Abstract

Study Analysis Group 21 (SAG21) of NASA’s Exoplanet Exploration Program Analysis Group was organized to study the effect of stellar contamination on space-based transmission spectroscopy, a method for studying exoplanetary atmospheres by measuring the wavelength-dependent radius of a planet as it transits its star. Transmission spectroscopy relies on a precise understanding of the spectrum of the star being occulted. However, stars are not homogeneous, constant light sources but have temporally evolving photospheres and chromospheres with inhomogeneities like spots, faculae, plages, granules, and flares. This SAG brought together an interdisciplinary team of more than 100 scientists, with observers and theorists from the heliophysics, stellar astrophysics, planetary science, and exoplanetary atmosphere research communities, to study the current research needs that can be addressed in this context to make the most of transit studies from current NASA facilities like Hubble Space Telescope and JWST. The analysis produced 14 findings, which fall into three science themes encompassing (i) how the Sun is used as our best laboratory to calibrate our understanding of stellar heterogeneities (‘The Sun as the Stellar Benchmark’), (ii) how stars other than the Sun extend our knowledge of heterogeneities (‘Surface Heterogeneities of Other Stars’), and (iii) how to incorporate information gathered for the Sun and other stars into transit studies (‘Mapping Stellar Knowledge to Transit Studies’). In this invited review, we largely reproduce the final report of SAG21 as a contribution to the peer-reviewed literature.

Details

Title
The effect of stellar contamination on low-resolution transmission spectroscopy: needs identified by NASA’s Exoplanet Exploration Program Study Analysis Group 21
Author
Rackham, Benjamin V 1   VIAFID ORCID Logo  ; Espinoza, Néstor 2   VIAFID ORCID Logo  ; Berdyugina, Svetlana V 3 ; Korhonen, Heidi 4   VIAFID ORCID Logo  ; MacDonald, Ryan J 5   VIAFID ORCID Logo  ; Montet, Benjamin T 6 ; Morris, Brett M 7 ; Oshagh, Mahmoudreza 8 ; Shapiro, Alexander I 9 ; Unruh, Yvonne C 10   VIAFID ORCID Logo  ; Quintana, Elisa V 11 ; Zellem, Robert T 12 ; Apai, Dániel 13 ; Barclay, Thomas 11 ; Barstow, Joanna K 14   VIAFID ORCID Logo  ; Bruno, Giovanni 15   VIAFID ORCID Logo  ; Carone, Ludmila 16 ; Casewell, Sarah L 17 ; Cegla, Heather M 18 ; Criscuoli, Serena 19 ; Fischer, Catherine 3 ; Fournier, Damien 9 ; Giampapa, Mark S 13 ; Giles, Helen 20 ; Iyer, Aishwarya 21 ; Kopp, Greg 22 ; Kostogryz, Nadiia M 9 ; Krivova, Natalie 9 ; Mallonn, Matthias 23 ; McGruder, Chima 24 ; Molaverdikhani, Karan 25   VIAFID ORCID Logo  ; Newton, Elisabeth R 26 ; Panja, Mayukh 9 ; Peacock, Sarah 11 ; Reardon, Kevin 27 ; Roettenbacher, Rachael M 28 ; Scandariato, Gaetano 15 ; Solanki, Sami 9 ; Stassun, Keivan G 29   VIAFID ORCID Logo  ; Steiner, Oskar 3 ; Stevenson, Kevin B 30 ; Tregloan-Reed, Jeremy 31   VIAFID ORCID Logo  ; Valio, Adriana 32 ; Wedemeyer, Sven 33 ; Welbanks, Luis 21 ; Yu, Jie 9 ; Alam, Munazza K 34 ; Davenport, James R A 35 ; Drake Deming 36 ; Dong, Chuanfei 37 ; Ducrot, Elsa 38 ; Fisher, Chloe 7 ; Gilbert, Emily 39 ; Kostov, Veselin 11 ; López-Morales, Mercedes 24 ; Line, Mike 21 ; Teo Močnik 40 ; Mullally, Susan 2 ; Paudel, Rishi R 11 ; Ribas, Ignasi 41 ; Valenti, Jeff A 2 

 Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, MA 02139 , USA 
 Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218 , USA 
 Leibniz-Institut für Sonnenphysik (KIS) , Schöneckstrasse 6, D-79104 Freiburg , Germany 
 European Southern Observatory (ESO) , Alonso de Córdova 3107, Vitacura, Santiago , Chile 
 Department of Astronomy, University of Michigan , 1085 South University Avenue, Ann Arbor, MI 48109 , USA 
 School of Physics, University of New South Wales , Sydney, NSW 2052 , Australia 
 Center for Space and Habitability, University of Bern , Gesellschaftsstrasse 6, CH-3012 Bern , Switzerland 
 Instituto de Astrofísica de Canarias , E-38200 La Laguna, Tenerife , Spain 
 Max-Planck-Institut für Sonnensystemforschung , Justus-von-Liebig-Weg 3, D-37077 Göttingen , Germany 
10  Department of Physics, Imperial College London , Prince Consort Road, London SW7 2AZ , UK 
11  NASA Goddard Space Flight Center , 8800 Greenbelt Road, Greenbelt, MD 20771 , USA 
12  Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109 , USA 
13  Steward Observatory, The University of Arizona , 933 North Cherry Avenue, Tucson, AZ 85721 , USA 
14  School of Physical Sciences, The Open University , Walton Hall, Milton Keynes MK7 6AA , UK 
15  INAF, Osservatorio Astrofisico di Catania , Via S. Sofia 78, I-95123 Catania , Italy 
16  Space Research Institute, Austrian Academy of Sciences , Schmiedlstrasse 6, A-8042 Graz , Austria 
17  School of Physics and Astronomy, University of Leicester , University Road, Leicester LE1 7RH , UK 
18  Department of Physics, University of Warwick , Coventry CV4 7AL , UK 
19  National Solar Observatory , 3665 Discovery Drive, Boulder, CO 80303 , USA 
20  Observatoire de Genève, Université de Genève , Chemin des Maillettes 51, CH-1290 Versoix , Switzerland 
21  School of Earth and Space Exploration, Arizona State University , 525 E. University Dr., Tempe, AZ 85281 , USA 
22  Laboratory for Atmospheric and Space Physics, University of Colorado Boulder , Boulder, CO 80303 , USA 
23  Leibniz-Institut für Astrophysik Potsdam (AIP) , An der Sternwarte 16, D-14482 Potsdam , Germany 
24  Center for Astrophysics | Harvard & Smithsonian , 60 Garden St, Cambridge, MA 02138 , USA 
25  Universitäts-Sternwarte, Ludwig-Maximilians-Universität München , Scheinerstrasse 1, D-81679 München , Germany 
26  Department of Physics and Astronomy, Dartmouth College , Hanover, NH 03755 , USA 
27  National Solar Observatory , Boulder, CO 80303 , USA 
28  Yale Center for Astronomy and Astrophysics, Yale University , 46 Hillhouse Avenue, New Haven, CT 06511 , USA 
29  Department of Physics and Astronomy, Vanderbilt University , Nashville, TN 37235 , USA 
30  Johns Hopkins University Applied Physics Laboratory , 11100 Johns Hopkins Road, Laurel, MD 20723 , USA 
31  Instituto de Investigación en Astronomia y Ciencias Planetarias, Universidad de Atacama , Copiapó, Atacama 1531772 , Chile 
32  Centro de Rádio Astronomia e Astrofisica Mackenzie, Mackenzie Presbyterian University , Rua da Consolacao, 896, Sao Paulo , Brazil 
33  Rosseland Centre for Solar Physics, University of Oslo , Postboks 1029 Blindern, 0315 Oslo , Norway 
34  Carnegie Earth & Planets Laboratory , 5241 Broad Branch Road NW, Washington, DC 20015 , USA 
35  Astronomy Department, University of Washington , Box 951580, Seattle, WA 98195 , USA 
36  Department of Astronomy, University of Maryland , College Park, MD 20742 , USA 
37  Department of Astronomy, Boston University , Boston, MA 02215 , USA 
38  Astrobiology Research Unit, Université de Liège , 19C Allée du 6 Aout, B-4000 Liège , Belgium 
39  Department of Astronomy and Astrophysics, University of Chicago , 5640 South Ellis Avenue, Chicago, IL 60637 , USA 
40  Gemini Observatory/NSF’s NOIRLab , 670 N. A’ohoku Place, Hilo, HI 96720 , USA 
41  Institut de Ciències de l’Espai (ICE, CSIC), Campus UAB , C/Can Magrans s/n, E-08193 Bellaterra , Spain 
Pages
148-206
Publication year
2023
Publication date
Jan 2023
Publisher
Oxford University Press
e-ISSN
27528200
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
3191358488
Copyright
© 2023 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.