Scientific Contributions and Mission Involvement
Over two decades, I have worked across multiple NASA missions and international collaborations, contributing scientific insight and technical leadership in the planning, processing, mining, and analysis of remote sensing data. My work spans the Earth, the outer solar system, and the Sun—linking physical modeling with high-performance computing and interactive data systems.
Earth Remote Sensing
AIRS (Atmospheric Infrared Sounder)
At NASA JPL, I led the development and maintenance of automated pipelines for generating all AIRS Level 2 products made publicly available through LANCE and GIBS. This required robust parallelized processing, enabling reprocessing of the entire mission archive (dating back to 2002) and real-time integration of new granules.
I created new visualizations and detection tools for transient atmospheric phenomena, including volcanic emissions and hydrological events. These tools allowed scientists and users to interactively explore and monitor atmospheric processes using near-real-time AIRS data.
MAIA (Multi-Angle Imager for Aerosols)
For MAIA, I developed the Instrument Targeting Tool, an interactive science planning system that supports mission design and observation sequencing. This tool integrates complex observation geometry and coverage constraints to optimize science return.
My contributions enabled planning teams to simulate and analyze orbital passes and evaluate trade-offs between competing observation priorities.
Plume Tracker
I contributed new algorithms and improvements to the Plume Tracker toolkit, used for retrieval of trace gas emissions (e.g., SO₂, CH₄) from radiative transfer analysis of satellite observations.
I enhanced its interactive and automated capabilities for both research workflows and operational products, expanding its ability to detect human-made and natural plumes in Earth’s atmosphere.
Solar Remote Sensing
Parker Solar Probe (WISPR) & Solar Orbiter (SoloHI)
For both WISPR and SoloHI, I developed algorithms and software for radiometric calibration, geometric mapping, visualization, and trajectory analysis of remote sensing observations of the Sun’s corona and solar wind.
These included novel methods to compensate for rapidly changing observation geometry as the spacecraft flew through structured plasma environments.
My work supported the production of calibrated imagery and derived data products that are published via SolarSoft for community use.
I also contributed to peer-reviewed studies using these products to track coronal ejecta, analyze heliospheric current sheet structure, and measure the dynamics of solar wind outflows. These efforts required detailed modeling of spacecraft trajectories, image registration, and solar emission models.
Planetary Remote Sensing
Cassini (VIMS, ISS, RADAR)
My longest-running work is with data from the Cassini spacecraft, especially through the VIMS (Visual and Infrared Mapping Spectrometer) instrument.
I developed titanbrowse, a database and visualization tool to explore hyperspectral observations of Titan’s surface and atmosphere.
This system supported dozens of research efforts by enabling scientists to mine vast volumes of spectral cubes, search spatially and spectrally, and visualize both raw and derived data.
I used radiative transfer modeling and principal component analysis (PCA) to retrieve atmospheric parameters—like methane and haze distributions—and to study the evolution of Titan’s cloud systems.
My work helped identify tropical lakes on Titan, a discovery that reshaped our understanding of methane’s surface-atmosphere cycle.
In addition, I contributed to the OMINAS toolkit, used to generate geometric overlays and science visualizations for Cassini’s imaging data, including products from the ISS camera and RADAR observations.
This involved handling spacecraft orientation, target body ephemerides, and observational metadata, often using the NAIF SPICE toolkit.
Astronomical and Solar System Observation Planning
I have also contributed to ground- and space-based telescope campaigns involving the Keck Observatory, the Hubble Space Telescope, and others, applying observation planning and modeling techniques to maximize data quality and science value.
In earlier roles, I worked on modeling asteroid fragment rotation and simulating asteroid collisions, including creating 3D visualizations and rotational dynamics simulations for rubble-pile bodies.
Technical Leadership Across the Remote Sensing Data Lifecycle
Across all missions, I have played a central role in the full remote sensing data lifecycle:
- Planning: Designing observation strategies and simulation tools
- Processing: Creating robust, parallelized pipelines for calibrated product generation
- Archiving: Developing structured databases with efficient access and search capabilities
- Mining: Applying spectral, statistical, and geometric methods to find features of interest
- Analysis: Integrating modeling, visualization, and algorithm development for scientific discovery
I specialize in bridging research and operations—bringing the rigor of scientific analysis into scalable, automated systems that enable broader use of complex datasets. Whether enabling new discoveries or building production systems, my work centers on empowering scientists and missions to make the most of their data.
Publications
See full list on Google Scholar, Researcher ID, or Scopus.
Selected Publications
- Structure of the Plasma near the Heliospheric Current Sheet as Seen by WISPR/Parker Solar Probe from inside the Streamer Belt
PC Liewer, A Vourlidas, G Stenborg, RA Howard, J Qiu, P Penteado, O Panasenco, CR Braga
The Astrophysical Journal (2023)
https://doi.org/10.3847/1538-4357/acc8c7 - Extracting the Heliographic Coordinates of Coronal Rays Using Images from WISPR/Parker Solar Probe
PC Liewer, J Qiu, F Ark, P Penteado, G Stenborg, A Vourlidas, JR Hall, P Riley
Solar Physics (2022)
https://doi.org/10.1007/s11207-022-02058-6 - Evolution of a streamer-blowout CME as observed by imagers on Parker Solar Probe and the Solar Terrestrial Relations Observatory
PC Liewer, J Qiu, A Vourlidas, JR Hall, P Penteado
Astronomy & Astrophysics (2021)
https://doi.org/10.1051/0004-6361/202039641 - Tracking solar wind flows from rapidly varying viewpoints by the Wide-field Imager for Parker Solar Probe
A Nindos, S Patsourakos, A Vourlidas, PC Liewer, P Penteado, JR Hall
Astronomy & Astrophysics (2021)
https://doi.org/10.1051/0004-6361/202039414 - Trajectory Determination for Coronal Ejecta Observed by WISPR/Parker Solar Probe
PC Liewer, J Qiu, P Penteado, JR Hall, A Vourlidas, RA Howard
Solar Physics (2020)
https://doi.org/10.1007/s11207-020-01715-y - Near-Sun observations of an F-corona decrease and K-corona fine structure
RA Howard et al., including P Penteado
Nature (2019)
https://doi.org/10.1038/s41586-019-1807-x - Simulating White Light Images of Coronal Structures for WISPR/Parker Solar Probe
P Liewer, A Vourlidas, A Thernisien, J Qiu, P Penteado, G Nisticò, R Howard
Solar Physics (2019)
https://doi.org/10.1007/s11207-019-1489-4 - A corridor of exposed ice-rich bedrock across Titan’s tropical region
CA Griffith, P Penteado et al.
Nature Astronomy (2019)
https://doi.org/10.1038/s41550-019-0756-5 - Current paradigms in parallelization: a comparison of vectorization, OpenMP and MPI
P Penteado
Journal of Computational Interdisciplinary Sciences (2015)
https://doi.org/10.6062/jcis.2012.03.03.0057 - Software and cyber-infrastructure development to control the Observatorio Astrofísico de Javalambre (OAJ)
Includes P Penteado
SPIE Proceedings (2014)
https://doi.org/10.1117/12.2054944 - Goals and strategies in the global control design of the OAJ Robotic Observatory
Includes P Penteado
Highlights of Spanish Astrophysics VII (2013)
ADS Link - Possible tropical lakes on Titan from observations of dark terrain
C.A. Griffith, J. Lora, J. Turner, P. Penteado et al.
Nature (2012)
https://doi.org/10.1038/nature11165 - Radiative transfer analyses of Titan’s tropical atmosphere
C.A. Griffith, L. Doose, M.G. Tomasko, P.F. Penteado et al.
Icarus (2012)
https://doi.org/10.1016/j.icarus.2011.11.034 - Latitudinal variations in Titan’s methane and haze from Cassini VIMS observations
P.F. Penteado et al.
Icarus (2010)
https://doi.org/10.1016/j.icarus.2009.11.003 - Ground-based measurements of the methane distribution on Titan
P.F. Penteado, C.A. Griffith
Icarus (2010)
https://doi.org/10.1016/j.icarus.2009.08.022 - VIMS spectral mapping observations of Titan during the Cassini prime mission
J.W. Barnes, P. Penteado et al.
Planetary and Space Science (2009)
https://doi.org/10.1016/j.pss.2009.04.013 - Characterization of Clouds in Titan’s Tropical Atmosphere
C.A. Griffith, P. Penteado et al.
The Astrophysical Journal Letters (2009)
https://doi.org/10.1088/0004-637X/702/2/L105 - Evidence for a Polar Ethane Cloud on Titan
C.A. Griffith, P. Penteado et al.
Science (2006)
https://doi.org/10.1126/science.1128245 - The Evolution of Titan’s Mid-Latitude Clouds
C.A. Griffith, P. Penteado et al.
Science (2005)
https://doi.org/10.1126/science.1117702 - Observations of Titan’s Mesosphere
C.A. Griffith, P. Penteado et al.
The Astrophysical Journal (2005)
https://doi.org/10.1086/444533 - Measurements of CH₃D and CH₄ in Titan from Infrared Spectroscopy
P.F. Penteado, C.A. Griffith, T.K. Greathouse, C. de Bergh
The Astrophysical Journal (2005)
https://doi.org/10.1086/444353 - Interacting ellipsoids: a minimal model for the dynamics of rubble-pile bodies
F. Roig, R. Duffard, P. Penteado, D. Lazzaro, T. Kodama
Icarus (2003)
https://doi.org/10.1016/S0019-1035(03)00216-1