Tom Barclay

Mission Operations Leader · Astrophysicist · Software Engineer

NASA Goddard Space Flight Center

I am the Project Science lead for operations for NASA's next flagship space observatory and have helped build, launch, and operate five space telescopes over the past 15 years. I help shape how the Roman Space Telescope will execute its largest survey programs, while also leading the software and planning systems behind mission operations for projects including Pandora. My work sits at the intersection of technical program leadership, mission operations, and hands-on engineering.

Tom Barclay
15+ Years at NASA
150+ Publications
31,000+ Citations
80 h-index
5 Space Missions

Missions & Leadership

I've led or contributed to five NASA flight missions since 2011 — from concept development through launch and operations — and support national security space coordination. Each has involved building software systems, leading cross-organizational teams, making high-stakes decisions under uncertainty, and representing NASA's interests with partners and contractors.

2022 – Present

Nancy Grace Roman Space Telescope

Operations Project Scientist

Primary Project Science Office point of contact for the Science Operations Center of NASA's next astrophysics flagship — a $4.3B wide-field infrared survey observatory targeting launch in late 2026. Project Science lead for the definition of Roman's Core Community Surveys (~75% of the first 5 years of operations), serve as Government Witness for SOC acceptance testing, and act as PI for multiple commissioning activities. Founded the Roman Community Forum and the Roman Technical Information GitHub repository.

2021 – Present

Pandora SmallSat

Deputy Project Scientist & SOC Lead

Led Science Operations Center development end-to-end — architecture design, interface control documents, and flight planning software — for this Astrophysics Pioneers Program mission studying stellar contamination of exoplanet spectra. Responsible for the development of the observation scheduling systems. Guided the mission through CDR, FRR, ORR, and successful launch on January 11, 2026 aboard a SpaceX Falcon 9. Currently supporting science operations.

2023 – Present

ULTRASAT

Participating Scientist

Contributing to NASA's participation in the Israeli-led Ultraviolet Transient Astronomy Satellite, a wide-field UV space telescope that will survey the transient sky. ULTRASAT will detect stellar explosions, merging neutron stars, and other time-domain events in the ultraviolet.

2017 – 2022

TESS (Transiting Exoplanet Survey Satellite)

Associate Project Scientist & GI Program Director

Served as Associate Project Scientist and founded the Guest Investigator Program, managing community access to TESS data and observations. Led the program through development and its primary mission phase, supporting hundreds of investigators worldwide. Co-led the discovery of TESS's first habitable-zone Earth-sized planet (TOI-700 d).

2011 – 2017

Kepler & K2

Guest Observer Office Director

Joined the Kepler mission at NASA Ames Research Center as a research scientist; promoted to Director of the Kepler/K2 Guest Observer Office in 2014. Led a team developing proposal calls, organizing reviews, and building community analysis software. Part of the small team that pioneered the K2 mission after loss of spacecraft fine pointing control. Served on the science and mission leadership teams.

Open Source Software

I've shipped production Python packages across four NASA missions — from observation schedulers and visibility tools to data analysis frameworks used by thousands. 94 repositories on GitHub, contributor to 4 NASA organizations.

Lightkurve

★ 380+  ·  1,200+ citations

Core developer of the standard Python package for analyzing time-series data from NASA's Kepler, K2, and TESS missions. Used by thousands of researchers worldwide. Features aperture photometry, systematics correction via linear algebra and Gaussian Processes, periodogram analysis, and pixel-level diagnostics.

PythonNumPySciPyMatplotlibAstropy

Kepler/K2 Community Tools

★ 119 (pyke)

Led development of the KeplerGO software suite — the official community tools for NASA's Kepler and K2 missions. Includes data reduction pipelines, field-of-view calculators, target pixel file animators, and publication tracking databases. Used by hundreds of astronomers for proposal preparation and data analysis.

PythonFITS I/OWCSPyPI

Selected Work

Over 150 refereed publications with 31,000+ citations (Google Scholar). Selected papers below highlight signal detection, statistical modeling, simulation, and open-source software.

IEEE Aerospace Conference, 2025

The Pandora SmallSat: A Low-Cost, High Impact Mission

First-author paper describing the end-to-end design, simulation tools, and management approach for the Pandora mission. Covers how the team built high-fidelity parameterized simulation and modeling tools to estimate performance, and how disruptive agile management delivered a 0.44 m space telescope on a SmallSat budget.

Barclay, Quintana, Colón et al. →
Nature, 2013

A Sub-Mercury-Sized Exoplanet (Kepler-37b)

Detected the smallest known planet by extracting an exoplanet transit signal with a depth of just 20 parts per million from noisy photometric data. Used asteroseismology to precisely characterize the host star and constrain the planet radius to smaller than Mercury.

Barclay, Rowe, Lissauer et al. →
ApJS, 2018 — 270+ citations

Predicting TESS Exoplanet Yields via Simulation

Built a large-scale Monte Carlo simulation of the TESS mission — synthesizing stellar populations, injecting planetary signals, and modeling detection pipelines — to predict the mission's planet yield. Predictions accurately matched actual discoveries years later.

Barclay, Pepper & Quintana →
AJ, 2020

TESS's First Habitable-Zone Earth-Sized Planet

Co-led the discovery and statistical validation of TOI-700 d, a 1.19 R⊕ planet receiving 86% of Earth's insolation. Combined multi-sector time-series analysis, Bayesian false-positive probability calculations, and ground-based follow-up to confirm the detection.

Gilbert, Barclay, Schlieder et al. →
Science, 2014

First Earth-Sized Planet in the Habitable Zone

Co-discovered Kepler-186f, a 1.1 R⊕ planet in the habitable zone of an M dwarf — proof that Earth-sized worlds exist where liquid water is possible. Required distinguishing a genuine signal from correlated noise in 4 years of photometry.

Quintana, Barclay, Raymond et al. →
ApJ, 2015

Oldest Known Terrestrial Planet System

Discovered Kepler-444, a system of five sub-Earth-sized planets orbiting an 11.2-billion-year-old star. Applied asteroseismic age-dating (Bayesian stellar modeling) to show Earth-sized worlds have formed throughout most of cosmic history.

Campante, Barclay, Swift et al. →

About

I'm an astrophysicist and mission operations leader at NASA's Goddard Space Flight Center, where I've been a civil servant since 2023. Before that I was a research scientist at UMBC/NASA (2017–2023) and at the BAER Institute/NASA Ames (2011–2017).

My day-to-day work focuses on the boundary between science and engineering — translating what astronomers need from a space telescope into the operational systems, survey designs, and planning software that make it happen. On Roman that means defining the mission's largest survey programs and ensuring the ground system can execute them; on Pandora it meant building the operations center from scratch and carrying it through launch.

My career spans the full space mission lifecycle — from proposal writing and requirements definition, through hardware I&T and launch, to operations and data analysis. I've led cross-organizational teams across NASA centers, contractors, and international partners. I also write production Python, build scheduling and planning tools, and have shipped open-source software across four NASA missions including Lightkurve (1,200+ citations).

My career spans the full space mission lifecycle — from proposal writing and requirements definition, through hardware I&T and launch, to operations and data analysis. I've led cross-organizational teams across NASA centers, contractors, and international partners. I also write production Python, build scheduling and planning tools, and have shipped open-source software across four NASA missions including Lightkurve (1,200+ citations).

I grew up in Sheffield, England. BSc Physics with Astrophysics, University of Leeds (2006); MSc, University of Manchester / Jodrell Bank (2007); PhD, University College London / Armagh Observatory (2011).

Awards & Selections

  • IEEE Aerospace Conference, Best Paper in Track (2025) — for "The Pandora SmallSat: A Low-Cost, High Impact Mission to Study Exoplanets and Their Host Stars"
  • NASA NEXT Program (2025) — selected for NASA's leadership development program
  • NASA Early Career Achievement Medal (2022)
  • ASD Peer Award (2019)
  • NASA Exceptional Public Service Medal (2017)
Tom Barclay at Kennedy Space Center

Core Competencies

Signal Detection & Time Series

Extracting weak, periodic, or transient signals from noisy, high-dimensional data. Transit detection, anomaly identification, and systematics modeling in multi-year photometric datasets.

Bayesian Inference & Modeling

MCMC, nested sampling, Gaussian Processes, hierarchical models. Designing probabilistic frameworks for parameter estimation and model comparison under uncertainty.

Python & Production Software

Shipped 12+ open-source Python packages across 4 NASA missions. Core developer of Lightkurve (1,200+ citations). Deep experience with NumPy, SciPy, pandas, scikit-learn, Poetry, CI/CD, and test-driven development.

Technical Program Leadership

End-to-end management of complex technical programs: requirements, milestones, risk, and cross-functional coordination across engineering, science, and operations teams of 50–200 people.

Simulation & Prediction

Large-scale Monte Carlo simulations to forecast mission performance. Population synthesis, injection-recovery testing, and forward modeling of instrument response.

Evaluation & Benchmarking

Designed evaluation frameworks and ran multi-year competitive review programs for three NASA missions. Built injection-recovery test pipelines, developed assessment rubrics, and made resource allocation decisions under competing priorities.

Strategic Focus Areas

Flagship Mission Operations

Ensuring Roman's science operations succeed from commissioning through routine observations. Translating complex mission requirements into operational systems that serve thousands of astronomers while meeting NASA's strategic objectives.

National Security Space

Applying mission operations expertise and technical leadership to national security space challenges. Experienced in classified coordination, inter-agency engagement, and bridging the gap between science missions and defense applications.

Next-Generation Mission Architecture

Shaping how future missions — from flagships to SmallSats — structure community engagement, operations models, and multi-center coordination. Contributing to strategic planning for NASA's astrophysics portfolio and the Habitable Worlds Observatory.

Cross-Organizational Technical Leadership

Leading teams across organizational boundaries — NASA centers, contractors, international partners — through ambiguous, high-stakes technical programs. Building consensus among stakeholders with competing priorities.