Sciences and Exploration Directorate

Giada Nicole Arney (she/her)

(Research AST, Planetary Studies)

Giada Nicole Arney (she/her)'s Contact Card & Information.
Phone: 301.614.6627
Org Code: 693
Mail Code 693
Greenbelt, MD 20771

Missions & Projects

Brief Bio

Dr. Arney is a Research Space Scientist in the Planetary Systems Laboratory at NASA Goddard Space Flight Center, with interests in astrobiology, planetary atmospheres, photochemistry, habitability, terrestrial solar system planets, exoplanets, and future large space telescopes. She obtained a dual-title PhD in astronomy and astrobiology from the University of Washington in 2016. She is a Deputy PI of the DAVINCI mission to Venus. Previously, she led the Science Support Analysis Team for the LUVOIR astrophysics flagship mission study. She has spoken at the Library of Congress and the Carnegie Institute in Washington, D.C. She received a NASA Early Career Achievement Medal in 2018 and was a recipient of the Presidential Early Career Award for Scientists and Engineers in 2019 (PECASE; and please see co-signed statement:

Research Interests

How do we find life on other worlds?

Solar System: Astrobiology

The search for life on other worlds is an exciting area of research, with implications across multiple branches of science. What biosignatures should we search for on exoplanets, and how do we detect them? I have modeled possible biosignatures of early Earth with a coupled photochemical-climate model and a spectral model, with an emphasis on the possible organic haze that possibly transiently existed in Earth's atmosphere during the Archean eon (~3.8-2.5 billion years ago). I helped develop the search strategy for biosignatures on exoplanets for the LUVOIR concept study, including leading chapter 3 of the LUVOIR interim and final reports ("Is there life elsewhere? Habitable exoplanet and solar system worlds"), and I presented the LUVOIR strategy for exoplanet and solar system world characterization to the 2020 Astronomy and Astrophysics decadal survey Panel on Electromagnetic Observations from Space 1. Previously, I helped lead a paper on Proxima Centauri b’s possible climatic and environmental states and their spectral discriminants, and I have been involved in work identifying oxygen false positive biosignature signals.

Enshrouded Planets

Solar System: Extrasolar Planets

My research has involved modeling and measuring properties of planets with an emphasis on worlds enshrouded by global cloud and haze layers because aerosols appear to be a common planetary phenomenon. I have a dual focus on both solar system bodies and on exoplanets. I have retrieved properties of Venus’ sub-cloud atmosphere through observations of its night side spectral windows, producing the first simultaneous and temporally resolved maps of cloud opacity, acid concentration, water vapor (H2O), hydrogen chloride (HCl), carbon dioxide (CO), carbonyl sulfide (OCS), and sulfur dioxide (SO2). I also have simulated hazy Archean Earth with a coupled photochemical-climate model, together with a spectral model, to study its atmospheric composition, climate, habitability, and observability.

Venus: Our Mysterious Neighbor

Solar System: Venus

Venus is Earth's nearest planetary neighbor, yet many questions remain about its physical and chemical state. Its obscuring, global cloud layers belie the complexity of the atmosphere lurking beneath. In my observations of the lower atmosphere, patterns of gases were observed that changed on a nightly basis (Earth nights, that is!). Apparent spatial anti-correlation between CO and OCS hint at a chemical relationship between these species in the deep atmosphere. There is much about Venus still to be understood.

Current Projects

The DAVINCI mission to Venus


I am excited to be serving as co-Deputy PI of the DAVINCI mission to Venus. DAVINCI is nominally scheduled to launch in mid-2029. Two flybys will occur in 2030, and observations of the clouds, the mysterious "unknown UV absorber", and night surface thermal emissivity during these flybys will provide new insights into the Venus atmosphere and surface environment. In mid-2031, a descent probe will be released into the Venus atmosphere above the Alpha Region tessera. During its hour-long transect through the atmosphere, five instruments on the probe will measure trace gases, isotopes, noble gases, and the physical state of the atmosphere in exquisite detail. A downward-looking camera will capture images of Alpha Regio, revealing new information about its composition and topography. Venus may once have been habitable, with oceans of liquid water, and the DAVINCI dataset will help reveal the true nature of Venus's evolution through time.

Photochemistry, Climate, Biosignatures, and Habitability

I am interested in how photochemical processes driven by different stellar spectra can affect the atmospheric compositions and environments of exoplanets, including their detectable biosigantures. I run 1-D photochemical-climate models to test these processes, and I am mentoring students working with these same models to tackle these types of questions. Currently, I am working with a team to model possible photochemically self-consistently atmospheric states analogous to Earth through time -- and their possible biosignatures -- for TOI-700 d, the first TESS rocky habitable zone planet, using a spectrum of TOI-700 recently obtained with the Hubble Space Telescope.


Ph.D. Astronomy and Astrobiology, University of Washington (2016)
Dissertation: Pulling Back the Veil: The Characterization and Habitability of Enshrouded Worlds

M.S. Astronomy, University of Washington (2012)

B.A. Astrophysics, with distinction, University of Colorado at Boulder (2009)
Linguistics minor

Professional Societies

Venus Exploration Analysis Group (VEXAG)

Steering Committee Member

2017 - 2021

Professional Service

  • Member: Habitable Worlds Observatory START team (2023 - present)
  • Lead: HabWorlds Observatory Biosignatures Science Task Group (2022-present)
  • Lead: HabWorlds Observatory Biosignatures Science Task Group (2022-present)
  • Deputy PI: DAVINCI mission (2021 - present)
  • SOC member.: Exoplanets in our Backyard 2.0 Workshop (2021 – 2022)
  • SOC member: NfoLD/NExSS Standards of Life Detection Workshop (2021)
  • Member: Venus panel for National Academy of Sciences Planetary Science and Astrobiology Decadal Survey for 2023-2032 (2020 – 2022)
  • Member: ExoPAG Science Interest Group III: Exoplanet / Solar System Synergies (2020 – present)
  • SOC member: 2021 Astrobiology Science Conference (2020 – 2021)
  • Deputy PI: DAVINCI+ mission concept Phase A study (2020 – 2021)
  • Co-lead organizer: Exoplanets in our Backyard Conference (2019 – 2020)
  • Participant: Early Career Focus Session for the Decadal Survey on Astronomy and Astrophysics (2018)
  • Co-lead: Science Task Group on AI Applications for Astrobiology at GSFC (2018 – 2019)
  • SOC member: 2019 Astrobiology Science Conference (2018 – 2019)
  • Mentor: Astrobiology team in the NASA/Google Cloud Frontier Development Laboratory (2018)
  • Lead: LUVOIR Science Support Analysis Team (2017 – 2019)
  • Planetary Science representative: GSFC Sellers Exoplanets Environments Collaboration (2017 – 2018)
  • Steering committee member: Venus Exploration Analysis Group (VEXAG) (2017 – 2021)
  • Co-editor: Planetary Astrobiology book: University of Arizona Press Space Science Series (2017 – 2019)
  •  Lecturer: Santander Astrobiology Summer School: Santander, Spain (June 2017)
  • Member: NASA GSFC Science Director’s Committee (2017 – 2019)
  • Task lead: Early Earth task of the Virtual Planetary Laboratory (2017 – present)
  • Co-lead organizer and public event lead: Comparative Climates of Terrestrial Planets III Conference (2017 – 2018)
  • SOC member: Venus Modeling Workshop (2016 – 2017)
  • Lead: VEXAG Early Career Scholars focus group (2016 – 2017)
  • Member: LUVOIR Science Support Analysis Team (2016 – 2017)
  • Member: LUVOIR exoplanets science working group (2016 – 2019)
  • Steering group student representative: University of Washington Astrobiology Program (2014 – 2016)
  • Planetarium Coordinator: University of Washington Astronomy Department (2013 – 2015)
  • SOC member and website lead: Astrobiology Graduate Conference (AbGradCon) (2011)


Honors and Awards:

·      Scialog Fellow for Signatures of Life in the Universe (2021)

·      Goddard Special Act Award: For major contributions as Deputy PI of the DAVINCI+ concept (2021)

·      Goddard Special Act Award: For distilling the Decadal white papers into essential guidance for Goddard Leadership (2020)

·      Robert H. Goddard Team Award: LUVOIR Science Support Analysis Team (2020)

·      NASA Group Achievement Award: Astrophysics Large Mission Study Team (2019)

·      Peer Award: NASA Goddard Planetary Science Division (2019)

·      NASA Early Career Achievement Medal (2018)

·      Kavli Fellow: National Academy of Sciences (2018)

·      Presidential Early Career Award for Scientists and Engineers (PECASE) (2019 award backdated to 2017; please see co-signed statement here:

·      NASA Astrobiology Institute Early Career Collaboration Award (2014)

·      Seattle Astronomical Society Outreach Award (2013)

·      Phi Beta Kappa (2008)


• NASA Postdoctoral Program Fellowship (2016)

• NSF Integrative Graduate Education and Research Traineeship (2010)



Photochemistry in TESS's first habitable zone terrestrial planet, TOI-700 d - Hubble Space Telescope Cycle 28 - Awarded: 0000-00-00

Other Professional Information

Public Outreach Experience

  • Live Shots: OSIRIS-REx sample return (2023)
  • Live Shots: DAVINCI mission (2023)
  • Guest Speaker: North County High School Astronomy class (2022)
  • Interviewee: NKH documentary on climate change (2021)
  • Interviewee: Curiosity Stream’s Breakthrough | Voyage to Venus episode (2021)
  • Guest Speaker: Curious Universe podcast on the DAVINCI mission (2021)
  • Guest Speaker: Spacechams podcast on the DAVINCI mission (2021)
  • Guest Speaker: Tech Girls International (2021)
  • Panelist: University of Washington Astronomy Department Alumni Career Options Colloquium (2021)
  • Guest Speaker: Seattle Astronomical Society Virtual Meeting (2021)
  • Participant: Reddit “AMA” for NASA Ocean Worlds Week (2020)
  • Guest Speaker: UC Berkeley Astrobiology Class (2020)
  • Guest Speaker: Death Valley National Park Dark Sky Festival (2020)
  • Guest Speaker: Girl Scouts troop (2019)
  • Participant: AGU Interview Series (2019)
  • Panelist: Awesome Con in Washington, D.C. (2019)
  • Panelist: “Space in Your Face” in Washington, D.C. (2018)
  • Participant: Reddit “AMA” for the NASA/Google Cloud Frontier Development Laboratory (2018)
  • Speaker: Indiana University TEDx conference (2018)
  • Lead organizer: English (30,300 views) and Spanish (10,900 views) NASA 360 Facebook Live panels for the Comparative Climates of Terrestrial Planets III meeting (2018)
  • Speaker: NASA 60th Anniversary Celebration “Science on a Sphere” talks (2018)
  • Panelist: Escape Velocity Conference (2018)
  • Panelist: Carnegie Corporation on Science and Society “Origins” Meeting in Washington D.C. (2018)
  • Guest Speaker: “STEMFems” group at Walt Whitman High School (2018)
  • Presenter: NASA Astrobiology and JWST booths at the US Science and Engineering Festival in Washington D.C. (2018)
  • Presenter: NASA Facebook Live TESS launch event (2018)
  • Panelist: SETI Facebook live event (2017)
  • Lecturer: Santander Astrobiology Summer School: Santander, Spain (2017)
  • Guest Speaker: NASA TV interview on habitable exoplanets (2017)
  • Guest Speaker: “Pale Rainbow Dots: The Search for Other Earths” public lecture at Carnegie Capital Science Event in Washington D. C. (2017)
  • Guest Speaker: “Identifying Habitable Worlds” public lecture in "Life As It Could Be: Astrobiology, Synthetic Biology, and the Future of Life" at the Library of Congress, Washington D. C. (2017)
  • Panelist: “Alien Climates on Planets Near and Far” panel at Awesome Con in Washington D. C. (2017)
  • Participant: NASA Reddit “AMA” for TRAPPIST-1 planet discovery (2017)
  • Presenter: Night Sky Network webinar on “Exploring Exoplanet Biosignatures, Potential ‘False Positives’ for Life, and the Case of Proxima Centauri b” (2016)
  • Presenter: Monthly planetarium shows at the University of Washington in Seattle, WA (2010 – 2016)
  • Presenter: “Astronomy on Tap” panel on “Life Under a Red Sun” about Proxima Centauri b in Seattle, WA (2016)
  • Consultant: “Alien Earths” exhibit at Pacific Science Center in Seattle, WA (2016)
  • Presenter: “Astronomy on Tap” presentation on “Hot Planets” about Venus and Earth climate change in Seattle, WA (2016)



2022. "Revealing the Mysteries of Venus: The DAVINCI Mission." The Planetary Science Journal 3 (5): 117 [10.3847/psj/ac63c2] [Journal Article/Letter]

2022. "Accurate Machine-learning Atmospheric Retrieval via a Neural-network Surrogate Model for Radiative Transfer." The Planetary Science Journal 3 (4): 91 [10.3847/psj/abe3fd] [Journal Article/Letter]

2022. "EarthShine: Observing our world as an exoplanet from the surface of the Moon." Journal of Astronomical Telescopes, Instruments, and Systems 8 (01): 014003 [10.1117/1.jatis.8.1.014003] [Journal Article/Letter]

2021. "No evidence of phosphine in the atmosphere of Venus from independent analyses." Nature Astronomy 5 (7): 631-635 [10.1038/s41550-021-01422-z] [Journal Article/Letter]

2021. "Nitrogen Dioxide Pollution as a Signature of Extraterrestrial Technology." The Astrophysical Journal 908 (2): 164 [10.3847/1538-4357/abd7f7] [Journal Article/Letter]

2021. "Claimed Detection of PH3 in the Clouds of Venus Is Consistent with Mesospheric SO2." The Astrophysical Journal Letters 908 (2): L44 [10.3847/2041-8213/abde47] [Journal Article/Letter]

2021. "The Fundamental Connections Between the Solar System and Exoplanetary Science." Journal of Geophysical Research: Planets 126 (2): e2020JE006643 [10.1029/2020je006643] [Journal Article/Letter]

2020. "The First Habitable-zone Earth-sized Planet from TESS. I. Validation of the TOI-700 System." The Astronomical Journal 160 (3): 116 [10.3847/1538-3881/aba4b2] [Journal Article/Letter]

2020. "The First Habitable Zone Earth-sized Planet from TESS. III: Climate States and Characterization Prospects for TOI-700 d." The Astronomical Journal 160 (118): 19pp. [10.3847/1538-3881/aba4b4] [Journal Article/Letter]

2020. "The Hubble Space Telescope's Near-UV and Optical Transmission Spectrum of Earth as an Exoplanet." The Astronomical Journal 160 (3): 100 [10.3847/1538-3881/aba0b4] [Journal Article/Letter]

2020. "Sensitive probing of exoplanetary oxygen via mid-infrared collisional absorption." Nature Astronomy 4 (4): 372-376 [10.1038/s41550-019-0977-7] [Journal Article/Letter]

2020. "Unifying themes and future work in planetary astrobiology." Planetary Astrobiology [Article in Book]

2020. "Venus as an Analog for Hot Earths." Planetary Astrobiology [10.2458/azu_uapress_9780816540068-ch014] [Article in Book]

2019. "The LUVOIR Extreme Coronagraph for Living Planetary Systems (ECLIPS) I: searching and characterizing exoplanetary gems." Techniques and Instrumentation for Detection of Exoplanets IX [10.1117/12.2530722] [Proceedings]

2019. "coronagraph: Telescope Noise Modeling for Exoplanets in Python." Journal of Open Source Software 4 (40): 1387 [10.21105/joss.01387] [Journal Article/Letter]

2019. "Venus as a Laboratory for Exoplanetary Science." Journal of Geophysical Research: Planets 124 (8): 2015-2028 [10.1029/2019je005939] [Journal Article/Letter]

2019. "An Ensemble of Bayesian Neural Networks for Exoplanetary Atmospheric Retrieval." The Astronomical Journal 158 (1): 33 [10.3847/1538-3881/ab2390] [Journal Article/Letter]

2019. "The L 98-59 System: Three Transiting, Terrestrial-size Planets Orbiting a Nearby M Dwarf." The Astronomical Journal 158 (1): 32 [10.3847/1538-3881/ab2459] [Journal Article/Letter]

2019. "The K Dwarf Advantage for Biosignatures on Directly Imaged Exoplanets." The Astrophysical Journal 873 (1): L7 [10.3847/2041-8213/ab0651] [Journal Article/Letter]

2018. "Evolved Climates and Observational Discriminants for the TRAPPIST-1 Planetary System." The Astrophysical Journal 867 (1): 76 [10.3847/1538-4357/aae36a] [Journal Article/Letter]

2018. "Exoplanet Biosignatures: A Review of Remotely Detectable Signs of Life." Astrobiology 18 (6): 663-708 [10.1089/ast.2017.1729] [Journal Article/Letter]

2018. "Exoplanet Biosignatures: Understanding Oxygen as a Biosignature in the Context of Its Environment." Astrobiology 18 (6): 630-662 [10.1089/ast.2017.1727] [Journal Article/Letter]

2018. "Constraining the climate and ocean pH of the early Earth with a geological carbon cycle model." Proceedings of the National Academy of Sciences 115 (16): 4105-4110 [10.1073/pnas.1721296115] [Journal Article/Letter]

2018. "Organic Haze as a Biosignature in Anoxic Earth-like Atmospheres." Astrobiology 18 (3): 311-329 [10.1089/ast.2017.1666] [Journal Article/Letter]

2018. "The Habitability of Proxima Centauri b: Environmental States and Observational Discriminants." Astrobiology 18 (2): 133-189 [10.1089/ast.2016.1589] [Journal Article/Letter]

2018. "Venus: The Making of an Uninhabitable World (white paper submitted in response to the solicitation of feedback for the "Astrobiology Science Strategy for the Search for Life in the Universe" by the National Academy of Sciences)." ArXiv e-prints [Full Text] [Report]

2018. "Explicit cloud representation in the Atmos 1D climate model for Earth and rocky planet applications." AIMS Geosciences 4 (4): 180-191 [10.3934/geosci.2018.4.180] [Journal Article/Letter]

2017. "Finding the Needles in the Haystacks: High-fidelity Models of the Modern and Archean Solar System for Simulating Exoplanet Observations." Publications of the Astronomical Society of the Pacific 129 (982): 124401 [10.1088/1538-3873/aa8fc4] [Journal Article/Letter]

2017. "Habitable Moist Atmospheres on Terrestrial Planets near the Inner Edge of the Habitable Zone around M Dwarfs." The Astrophysical Journal 845 (1): 5 [10.3847/1538-4357/aa7cf9] [Journal Article/Letter]

2017. "Pale Orange Dots: The Impact of Organic Haze on the Habitability and Detectability of Earthlike Exoplanets." The Astrophysical Journal 836 (1): 49 [10.3847/1538-4357/836/1/49] [Journal Article/Letter]

2016. "The Pale Orange Dot: The Spectrum and Habitability of Hazy Archean Earth." Astrobiology 16 (11): 873-899 [10.1089/ast.2015.1422] [Journal Article/Letter]

2016. "IDENTIFYING PLANETARY BIOSIGNATURE IMPOSTORS: SPECTRAL FEATURES OF CO AND O 4 RESULTING FROM ABIOTIC O 2 /O 3 PRODUCTION." The Astrophysical Journal 819 (1): L13 [10.3847/2041-8205/819/1/l13] [Journal Article/Letter]

2016. "IS THE PALE BLUE DOT UNIQUE? OPTIMIZED PHOTOMETRIC BANDS FOR IDENTIFYING EARTH-LIKE EXOPLANETS." The Astrophysical Journal 817 (1): 31 [10.3847/0004-637x/817/1/31] [Journal Article/Letter]

2015. "3D MODELING OF GJ1214b's ATMOSPHERE: FORMATION OF INHOMOGENEOUS HIGH CLOUDS AND OBSERVATIONAL IMPLICATIONS." The Astrophysical Journal 813 (1): L1 [10.1088/2041-8205/813/1/l1] [Journal Article/Letter]

2014. "Spatially resolved measurements of H2O, HCl, CO, OCS, SO2, cloud opacity, and acid concentration in the Venus near-infrared spectral windows." Journal of Geophysical Research: Planets 119 (8): 1860-1891 [10.1002/2014je004662] [Journal Article/Letter]

Talks, Presentations and Posters



October 2021

Space Telescope Science Institute. Baltimore, MD. Virtual.

Venus: The Exoplanet in our Backyard.


University of Washington Astrobiology Colloquium. Seattle, WA. Virtual.

Venus: The Exoplanet in our Backyard

December 2020

DPS Meeting Virtual Plenary.

Lessons from Earth History for Exoplanets

December 2020

Seminar for Harvard EPS Department. Cambridge, MA. Virtual.

DAVINCI+ and the Search for Exoplanets.

September 2020

Exoplanet Analysis Group (ExoPAG) virtual presentation.

False Positives and False Negatives: Cousins of Antibiosignatures.

June 2020

University of Chicago “What Makes a Planet Uninhabitable?” meeting. Virtual.

The Story of Life in the Universe with LUVOIR.

July 2019

Astrobiology Science Conference.  Bellevue, WA.

Characterizing Other Earths.

May 2018

Planetary Habitability Workshop. Leiden, The Netherlands.

The Pale Orange Dot

March 2018

Georgia Tech School of Earth and Atmospheric Science Seminar Series.

Pale Rainbow Dots: The Search for Other Earths

November 2017

Carnegie Capital Science Event. Carnegie Institution for Science, Washington D. C.

The Hunt for Alien Earths

November 2017

Planetary Astronomy Seminar. University of Maryland, College Park, MD.

Identifying Habitable Worlds

October 2017

Astrobiology Symposium: "Life As It Could Be: Astrobiology, Synthetic Biology, and the Future of Life.” The Library of Congress, Washington D. C.

The Habitability and Characterizaton of Enshrouded Worlds

June 2017

NASA Goddard Solar System Exoploration Seminar.

Pulling Back the Veil: The Characterization and Habitability of Enshrouded Worlds.

May 2017

Space Telescope Science Institute Exoplanet Seminar.

Pulling Back the Veil: What Can LUVOIR Teach Us About Enshrouded Earths?

April 2017

LUVOIR Seminar. NASA Goddard Space Flight Center, Greenbelt, MD.

Pale Orange Dots

April 2017

Carnegie Institution Department of Terrestrial Magnetism. Washington, D. C.

Pulling Back the Veil: Characterizing Enshrouded Worlds

August 2016

Stars and Planets Seminar. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA.

The Pale Orange Dot: The Spectrum and Climate of Hazy Archean Earth

December 2015

Solar System Exploration Fall Seminar Series. NASA Goddard Space Flight Center, Greenbelt, MD.

Ground Based Measurements of Trace Gases Below the Cloud Deck

November 2015

13th Meeting of the Venus Exploration Analysis Group Meeting. Washington, D.C.


Organic Haze as a Biosignature in the Presence of Biogenic Sulfur Gases.

May 2017

AbSciCon, Mesa, AZ. April 2017. Oral Presentation.

Pale Orange Dots: Earthlike Worlds with Organic Hazes

March 2016

The Astrophysics of Planetary Habitability Conference, Vienna, Austria. February 2016. Oral presentation.

Under an Orange Sky: The Many Implications of Organic Haze for Earthlike Planets

December 2015

DPS, National Harbor, MD. Oral presentation

Under an Orange Sky: The Many Implications of an Archean Haze.

October 2015

Comparative Climates of Terrestrial Planets II. Mountain View, CA. Oral presentation.

The Pale Orange Dot: Spectra and Climates of Hazy Archean Earthlike Worlds

July 2015

AbSciCon, Chicago, IL, Oral Presentation.

The Pale Orange Dot: The Climactic and Spectral Effects of Haze in Archaen Earth's Atmospher

June 2015

Emerging Researchers in Exoplanet Science Symposium, State College, PA, Oral Presentation.

Hazy Archean Earth as an Analog for Hazy Earthlike Exoplanets

February 2015

 225th AAS Meeting, Seattle, WA, Oral presentation.

Spatially-Resolved Measurements of H2O, HCl, CO, OCS, SO2 and cloud opacity in the Venus Near-Infrared Windows

November 2013

DPS, Denver, CO, Oral presentation.