Nathan Roth

Dr. Roth is a Research Assistant Professor in the Department of Physics at American University. He works full-time in the Astrochemistry Laboratory at the NASA Goddard Space Flight Center in Greenbelt, MD. He is an expert in near-infrared spectroscopy and millimeter-wave interferometry of small bodies.

Dr. Roth maintains observing programs with radio and near-infrared observatories around the world and in space, including the Atacama Large Millimeter Array (ALMA), the Northern Extended Millimeter Array (NOEMA), the Submillimeter Array (SMA), the Very Large Array (VLA), the Atacama Pathfinder Experiment (APEX), the Arizona Radio Observatory (ARO), the Green Bank Telescope (GBT), the NASA Infrared Telescope Facility (IRTF), and the James Webb Space Telescope (JWST).

His research objective is to trace astrochemistry throughout the stellar lifecycle by exploiting connections between primitive solar system bodies and protoplanetary, protostellar, and interstellar environments. Leveraging synergies between molecular spectroscopy at radio and near-infrared wavelengths, his research explores the lineage of volatile and refractory organics from the interstellar medium to the present-day solar system, thereby improving our understanding of planetary system formation.

Mentoring:

Lillian Hart (2025-present): University of Maryland

Jesse Bier (2024-present): University of Missouri-St. Louis

Eli Rockenbeck (2024-2025): American University

Kiernan Foster (2023-present): University of Virginia

Christine Mlynek (2023): United States Naval Academy

Timothy Proudkii (2021-present): Virginia Tech/California Institute of Technology

Ph.D. in Physics, July 2019, Missouri University of Science & Technology and University of Missouri-St. Louis Joint Physics Program, Rolla, MO

Journal Referee:

Astronomical Journal

Planetary Science Journal

Astronomy & Astrophysics

Selected Professional Activities:

American Astronomical Society DPS Press Officer (Incoming - 2025)

Investigation Team Member, Double Asteroid Redirection Test (DART) mission

Science Co-Investigator, SALTUS Astrophysics Probe mission concept

JWST Cycle 1 Solar System GTO Team

Principal Investigator, JWST Cycle 1 GO 1897

Co-Investigator, JWST GTO 1253, GO 3399, 1566, 2337

American Astronomical Society DPS 2023 Meeting: SOC, VOC

Infrared Science and Technology Integration Group (IR STIG) Leadership Council

NRAO ALMA Ambassador, ALMA Cycle 9

Speaker, "An Evening with NASA Scientists and Engineers" Senior Outreach Series, DART Mission Update, February 2023

American University Physics Senior Capstone Course Mentor

NASA Neurodiversity Network (N3) Mentor

NASA Goddard Space Flight Center/United States Naval Academy Internship Mentor

NASA Office of STEM Engagement Mentor

NASA CONNECTORS Program Mentor

Reviewer, NASA ROSES, NSF

White Paper Lead to the Planetary Science and Astrobiology Decadal Survey (2023-2032)

Robert H. Goddard Award -- Exceptional Achievement for Mentoring, 2023

Asteroid 33484 Nathanroth (1999 GS7), 2023

Ciel deGutis Award for Research Excellence, 2019, University of Missouri-St. Louis

Successful Observing Proposals:

2025, ALMA Cycle 11 2024.A.00049.S, PI, Director's Discretionary Time, Coordinated ALMA and JWST Observations of Interstellar Comet 3I/ATLAS

2025, ALMA Cycle 11 2024.A.00023.S, PI, Director's Discretionary Time, ALMA Imaging of Sungrazing Comet C/2024 G3

2024, ALMA Cycle 11 2024.1.00885.S, PI, ALMA NH₂D Imaging in Exceptional Comet C/2023 A3: Coordinated Studies with VLA and NASA IRTF

2024, ALMA Cycle 11 2024.1.00477.T, Co-I, Direct Sublimation vs. Gas-Phase Coma Synthesis - The Missing Link in Cometary Science

2024, ALMA Cycle 11 2024.1.00137.T, Co-I, Revealing the Primitive Origins of Cometary Ices

2024, ALMA Cycle 11 2024.1.00104.S, Co-I, Uranus' Polar Bullseye

2024, Very Large Array VLA/24B-413, PI, Multiband Thermal Photometry of Near Earth Asteroids with VLA

2024, Very Large Array VLA/24A-458, PI, Director's Discretionary Time, Imaging NH₃ in Comet 12P Coordinated VLA/IRTF/SMA/ALMA Large Program Studies

2024, Green Bank Telescope GBT/24B-396, PI, First Maps of Cometary NH₃: VLA + GBT Spectra of Exceptional Comet C/2023 A3

2024A, Submillimeter Array, PI, Joint SMA/VLA Studies of Exceptional Comet C/2023 A3

2023, Very Large Array VLA/24A-377, PI, First Maps of Cometary NH₃: VLA Imaging of Exceptional Comet C/2023 A3

2023, ALMA Cycle 10 2023.1.00703.S, PI, Revealing the Outgassing Mechanisms of Mega-Comet C/2014 UN271: Spectrally Resolved CO and Synergy with JWST

2023, ALMA Cycle 10 Large Program 2023.1.01143.L, Co-I, The Large 12P COMA Survey (COmetary Molecules with ALMA)

2023B, Submillimeter Array, PI, Coordinated SMA/ALMA Studies of 12P/Pons-Brooks

2023B, Submillimeter Array, PI, SMA Wideband Subsurface Thermal Studies of NEAS

2023, Northern Extended Millimeter Array, PI, Subsurface Thermal Studies of NEAs: Planetary Defense and Relevance to ESA/Hera

2023, Northern Extended Millimeter Array, Co-I, Characterization of the nucleus and coma of comet 12P (Pons-Brooks)

2023, Institut de Radioastronomie Millimetrique, Co-I, Composition of Halley class comet 12P/Pons-Brooks

2023B, NASA IRTF, Co-I, Investigating Changes in Volatile Production and Mixing Ratios of Comet 103P/Hartley 2: A Multi-Epoch Analysis with iSHELL

2023B, NASA IRTF, Co-I, Comet 2P/Encke: Investigating Possible Causes for the Unusual Compositional Variability in a Short Period Comet

2023A, NASA IRTF, PI, iSHELL Studies of Bright Comet C/2022 E3: Multi-Molecule Coma Thermal Physics and Coordination with JWST

2023A, NASA IRTF, Co-I, SpeX observations of C/2022 E3 (ZTF) and C/2021 T4 (Lemmon): Exploring the overall coma composition of comets

2023A, NASA IRTF, Co-I, First Measurements of Parent Volatile Composition of Anomalous Comet 96P/Machholz

2022, James Webb Space Telescope GO 3399, Co-I, An Empirical Calibration of the NIRSpec IFU Point Spread Function to Enable High Contrast Imaging Spectroscopy

2022, Northern Extended Millimeter Array, PI, Coordinated NOEMA/JWST Studies of Comet C/2022 E3: Inner Coma Thermal Physics and a Window into Sulfur Chemistry

2022B, Submillimeter Array, PI, Coordinated SMA/JWST Studies of Comet C/2022 E3: Inner Coma Thermal Physics and a Window into Sulfur Chemistry

2022, ALMA Cycle 9 2022.1.01084.S, PI, Revealing the Outgassing Mechanisms of Mega-Comet C/2014 UN271: A Deep Search for CO with ALMA

2022, Atacama Pathfinder Experiment, PI, APEX Monitoring Observations of Comet C/2017 K2 in Support of ALMA

2022, Atacama Pathfinder Experiment, PI, A Search for Distributed Sources in a Target of Opportunity Comet

2022, ALMA Cycle 8 2021.A.00013.S, Director's Discretionary Time, PI, ALMA Observations of the DART Mission: Revealing Composition of the Impact Ejecta and the Interior of S-Type Asteroids

2022B, Green Bank Telescope, PI, Measuring NH3 and OH in a Target-of-Opportunity Comet with the GBT

2022, Northern Extended Millimeter Array, PI, A Search for Distributed Sources at Small Heliocentric Distance in Oort Cloud Comet C/2021 O3 (PanSTARRS)

2022A, Green Bank Telescope, PI, Measuring NH3 and OH in a Target-of-Opportunity Comet with the GBT

2022, NASA IRTF, Co-I, Investigation of CO vs H2O driven outgassing in comet C/2017 K2 (PanSTARRS)

2022, NASA IRTF, Co-I, Study of the composition and outgassing behavior of comet C/2021 O3 (PanSTARRS) at small heliocentric distances

2021, ALMA Cycle 8 2021.1.00862.S, PI, The Evolution of Molecular Outgassing in Distant Comet C/2017 K2: A Joint ALMA/JWST Monitoring Campaign Across Ice Lines

2021, James Webb Space Telescope GO 1897, PI, Pushing the Envelope of the JWST Discovery Space: Measuring the Insoluble Organic Matter (IOM) and Polycyclic Aromatic Hydrocarbon (PAH) Content of Comet 9P/Tempel 1

2021, Submillimeter Array, PI, A Search for Distributed Sources at Small Heliocentric Distance in Comets C/2021 A1 (Leonard) and C/2021 O3 (PanSTARRS)

2021, ALMA Cycle 8 2021.1.00985.T, Co-I, Volatile composition of a ToO Interstellar Object: Comparison to Disk and Comet Chemistry

2021, ALMA Cycle 8 2021.1.00911.T, Direct Sublimation vs. Gas-Phase Synthesis: A Comet ToO Proposal

2021, ALMA Cycle 8 2021.1.00828.S, Validating the range of D/H ratios in our Solar System's primitive H2O reservoir

2021B, NASA IRTF, PI, Bridging the ''Rosetta Stone'' of Cometary Science: A Multi-Wavelength, Multi-Epoch Campaign Toward Comet 67P/Churyumov-Gerasimenko During its First Apparition Since the Conclusion of the Rosetta Mission

2021B, NASA IRTF, PI, Director's Discretionary Time Observations of Centaur 29P/Schassmann-Wachmann-1 During Its Extraordinary Outburst

2021B, Atacama Pathfinder Experiment, PI, A Search for Distributed Sources in a Target of Opportunity Comet

2021B, Atacama Pathfinder Experiment, PI, Unraveling Comet Photochemistry in Oort Cloud Comet C/2021 A1 (Leonard)

2021, James Webb Space Telescope, GTO 1253, Co-I, Target of Opportunity Comet

2021, James Webb Space Telescope GO 2377, Co-I, Composition of an Interstellar Object -- Unique Insights into Protoplanetary Disk Midplane Chemistry

2021, James Webb Space Telescope GO 1566, Co-I, The Coma Dust and Volatiles of C/2017 K2 (Pan-STARRS)

2021B, NASA IRTF, Co-I, Comprehensive compositional study of exceptionally bright comet C/2021 A1 (Leonard)

2021B, NASA IRTF, Co-I, Characterizing the Parent Volatile Composition and Outgassing of a Target-of-Opportunity Comet

2021, Green Bank Observatory, PI, Mapping NH$_3$ in a Target-of-Opportunity Comet: A Joint GBT/VLA Proposal

2021, IRAM 30m, Co-I, Ground-based truth of the composition of Rosetta target 67P/Churyumov-Gerasimenko

2021, W. M. Keck Observatory, Co-I, Keck/NIRSPEC observations of Rosetta target 67P: The missing link between ground-based and in-situ databases of cometary volatiles

2021, Northern Extended Millimeter Array, PI, The Transition from CO- to H₂O-Dominated Outgassing in Recently Discovered Oort Cloud Comet C/2021 A1 (Leonard)

2021, Arizona Radio Observatory, PI, Monitoring the Activity and Composition of Newly Discovered Oort Cloud Comet C/2021 A1 (Leonard)

2021, Arizona Radio Observatory, PI, Monitoring the Molecular Activity of a Bright ToO Comet

2021, Atacama Pathfinder Experiment, PI, A Search for Distributed Sources in a Target of Opportunity Comet

2021, Northern Extended Millimeter Array, PI, The Evolution of Molecular Outgassing in Distantly Active Comet C/2017 K2: A Joint NOEMA/JWST Monitoring Campaign Across Ice Lines

2021, NASA IRTF, Co-I, Characterizing Parent Volatile Composition and Outgassing in a Target-of-Opportunity Comet

2020, NASA IRTF, PI, Director's Discretionary Time Proposal for Comet C/2020 S3 (Erasmus)

2020B, Arizona Radio Observatory, PI, Monitoring the Molecular Activity of a Bright ToO Comet

2020A, Arizona Radio Observatory, PI, Monitoring the Activity and Composition of Bright Comet C/2017 T2 (PanSTARRS)

2020A, Arizona Radio Observatory, PI, Monitoring the Activity and Composition of Newly Discovered Comet C/2019 Y4 (ATLAS)

2020A, Atacama Pathfinder Experiment, PI, A Search for Distributed Sources in a Target of Opportunity Comet

2019, Atacama Pathfinder Experiment, PI, A Coordinated Molecular Survey of Interstellar Comet 2I/Borisov

2019, Atacama Large Millimeter Array, Co-I, Direct Sublimation vs. Gas-Phase Synthesis: A Comet ToO Proposal

2019, Institut de Radioastronomie Millimetrique, Co-I, The activity and composition of Interstellar Comet C/2019 Q4 (Borisov)

2019, Institut de Radioastronomie Millimetrique, Co-I, Composition and the origin of formaldehyde in a bright comet

2019, NASA IRTF, Co-I, A Study of Volatile Composition and Possible Asymmetries in C/2017 T2 (PanSTARRS)

2019, NASA IRTF, Co-I, Probing the Compositional Heterogeneity of C/2016 R2 (PanSTARRS) using iSHELL and Spitzer

2019, NASA IRTF, Co-I, Continuing the Study of 46P/Wirtanen During Its Historic Apparition: Volatile Composition and Testing for Variability

2018, Institut de Radioastronomie Millimetrique, Co-I, Composition of comet 21P/Giacobini-Zinner and its long-term evolution

2018, NASA IRTF, PI, Testing Seasonal and Evolutionary Effects on Volatile Composition in the Prototypical Carbon-Chain Depleted Comet 21P/Giacobini-Zinner

2018, NASA IRTF, PI, Probing the Evolutionary History of Comets: An Investigation of the Hypervolatiles CO and CH₄ and Parent Volatile Abundances in the Jupiter-family Comet 21P/Giacobini-Zinner

2018, W. M. Keck Observatory, Co-I, Parent Volatiles, Near-Nucleus Environment, and Outgassing in Comet 46P/Wirtanen: A Historic Apparition for a Space Mission Priority Target

2018, NASA IRTF, Co-I, The Coma Physical Environment and Water Outgassing in Comets 46P/Wirtanen and 21P/Giacobini-Zinner: Two Outstanding Apparitions of Potential Spacecraft Targets

2018, NASA IRTF, Co-I, A Collaborative Study of the Chemistry of Comet Wirtanen During Its Exceptional 2018 Apparition

2018, NASA IRTF, Co-I, Measuring the CO and CH₄ Abundance in Jupiter family Comet 46P/Wirtanen

2018, NASA IRTF, Co-I, Parent Volatile Abundances and Inner-Coma Physics in Comet C/2017 S3 (PanSTARRS)

2018, NASA IRTF, Co-I, Measurement of Parent Volatiles in Halley-family comet 38P/Stephan-Oterma and Jupiter-family comet 64P/Swift-Gehrels

2018, NASA IRTF, Co-I, SpeX observations of the overall gas and dust composition of five comets during the unusually rich 2018B observing semester

2017, NASA IRTF, PI, Parent Volatile Abundances and Behavior of Volatile Release in Comets 2P/Encke and 45P/Honda-Mrkos-Pajdusakova

2017, NASA IRTF, PI, Target of Opportunity Request for Comet C/2015 V2 (Johnson)

2017, NASA IRTF, Co-I, The Inner Coma Physical Environment of Ecliptic Comets 45P/Honda-Mrkos-Pajdusakova, 41P/Tuttle-Giacobini-Kresak, and 2P/Encke

2017, NASA IRTF, Co-I, Parent Volatile Abundances and Inner-Coma Physics in Comets C/2015 V2 and C/2015 ER61

2017, NASA IRTF, Co-I, SpeX observations of the overall gas and dust composition of five comets during the unusually rich 2017A observing semester