Scientist (Astrophysics & Earth Sciences)
NASA's Jet Propulsion Laboratory
- Science Engagement Co-Lead and Project Science Team Member, NASA’s Habitable Worlds Observatory
- Scientist, JPL Greenhouse Gas (GHG) Team, NASA’s EMIT Imaging Spectrometer
- Science Team Member, CASE
- Organizing Committee Member, NASA’s Exoplanets Explorers Science Series
About me
I am a scientist specializing in characterizing the atmospheres of exoplanets, which are planets outside the Solar System. My work involves using space missions to study these distant worlds and mapping pollutants on Earth through imaging spectroscopy as part of NASA's EMIT mission. Driven by the question "Is there life out there", I pursued a career in astronomy. I was born in Brazil and I did my B.S. in Physics at the University Federal of Rio Grande do Norte, in the northeast of Brazil. Then I moved to Sao Paulo where I completed my master (2017) and Ph.D. (2020) on the characterization of exoplanets atmospheres and habitability. I started a postdoc at NASA/JPL in 2020, where I continued to study the atmospheres of exoplanets. As an astronomer, I've come to quickly understand the preciousness of life in the universe, recognizing that so far, Earth stands as the sole known to host life. It's my job to take care of our unique planet and of the diverse lifeforms that co-habit the planet with us. Thus, drawing from my expertise in investigating the compositions of distant exoplanets, I now employ a similar methodology to assess pollutant distribution on Earth.
This methodology, known as spectroscopy, allows for the identification of molecules based on their absorption of specific wavelengths of light. Instruments like the Hubble and James Webb Space Telescopes have successfully utilized spectroscopy to discern the presence of water, methane, and other compounds in exoplanet atmospheres. Applying this technique to Earth, we can observe the signatures of greenhouse gases like methane and CO2 through their reflectance of light.
Education
NASA Postdoctoral Fellow
JPL Postdoctoral Fellow
NASA's Jet Propulsion Laboratory
Ph.D. Geospatial Sciences and Applications
Mackenzie Presbyterian University (Brazil)
Master Geospatial Sciences and Applications
Mackenzie Presbyterian University (Brazil)
Bachelor in Physics
Federal University of Rio Grande do Norte (Brazil)
Research
Astrophysics
Observation of Exoplanets' Atmospheres
I'm part of the developer team of the EXCALIBUR pipeline (EXoplanet CALIbration and Bayesian Unified Retrieval) that performs a uniform analysis of transit spectroscopy using a combination of data from the Hubble Space Telescope Telescope (HST/STIS and /WFC3) and Spitzer for a diverse sample of ~100 of exoplanets, spanning a wide range of planet masses, radii, and equilibrium temperatures.
Exoplanets Habitability
To provide insights on the influence of stellar activity on habitability, during my Ph.D. I quantified the impact of UV radiation from superflares on living organisms on planets in the Habitable Zone (HZ) of the flaring stars Kepler-96 and Trappist-1. For that, I estimated the increase in the UV spectra (100-400nm) due to the superflares. I used a radiative transfer code to calculate the attenuation of the UV by the planetary atmosphere. Using that, I estimated the fluxes arriving at the planet's surface and in a hypothetical ocean. I found that for Kepler-96 (solar type), the UV augmented by the flare is higher, and the microorganisms need protection from an ozone layer to live on the surface of the planet. However, they could escape from the hazardous UV effects at depths deeper than 10m below the ocean surface. While for, Trappist-1's UV fluxes are lower and resistant lifeforms can survive even on a planet without ozone.
Publications:
Surface and Oceanic Habitability of Trappist-1 Planets under the Impact of Flares
Atmospheric Evolution
The context of a planet's formation and its evolutionary history is crucial for interpreting measurements of exoplanet atmospheric composition. Particularly, the atmospheres of rocky planets can evolve from their primordial states to secondary compositions due to atmospheric erosion, or geological processes, including volatile delivery from impacts and outgassing. The field is now in the process of looking into several factors that shape the atmospheres of these planets to answer: 1) How do the atmospheres of rocky planets form and evolve? 3) Are their evolution different from the terrestrial Solar System planets?
To shed light on these questions, I conducted exoplanet population studies focusing on their properties as indicators of envelope evolution in small planets, including super-Earths and sub-Neptunes. During my Ph.D., I analyzed real planets sourced from the NASA Exoplanet Archive, exploring various factors as evolutionary markers, such as density, irradiation, radius, mass, and EUV fluxes. I have also focused on modeling the atmospheric erosion on the population of small exoplanets and HZ planets orbiting M dwarfs due to stellar wind, and XEUV-driven escape throughout their lifetime.
Publications:
Impact of M-dwarf stellar wind and photoevaporation on the atmospheric evolution of small planets
Earth Sciences
Mapping Plastic Pollution Worldwide with NASA's EMIT mission
I also conduct research in imaging spectroscopy with NASA's EMIT mission, where I focus on mapping pollutants in our planet. The EMIT imaging spectrometer is aboard the International Space Station and it was originally launched with the goal of understanding how dust loft from the surface affects the climate. However, EMIT also has shown the ability to map pollutants, such as emissions of greenhouse gases. I'm now exploring a new ability of EMIT: mapping plastic polution worldwide.
Media
English Interviews:
New York Times - Alarmed by Climate Change, Astronomers Train Their Sights on Earth
Astronomy Magazine - Volcanoes could have breathed new life into a super-Earth’s atmosphere
WiRed magazine - Did This Scorching-Hot Planet Lose—and Regain—an Atmosphere?
Hubble Press Release - Distant Planet May Be On Its Second Atmosphere, NASA's Hubble Finds
LUNATICS Astrobiologist of the Month (October 2023 New Moon)
Interview to Podcast Exploring Astrophysics
Portuguese Interviews:
Conheça a nordestina que trabalha na Nasa em pesquisa com telescópio Hubble
Revista Fapesp: Dados do Universo
Rádio Camara: Um mundo melhor tem mulheres em todos os lugares
Revista Mackenzie: Donas da Pesquisa
Pesquisadora paraibana faz parte de equipe da NASA que fez descoberta sobre regeneração de atmosfera
Raissa Estrela © 2024