15 citations · 49 across the 18 of their papers we have counts for
21 papers
JWST Reveals Refractory-Rich Water Ice in Interstellar Comet 3I/ATLAS: Evidence for a Continuum of Grain Properties across Protoplanetary Disks
Silvia Protopapa, Michael S. P. Kelley, Martin A. Cordiner +12
We present JWST/NIRSpec PRISM observations of the interstellar comet 3I/ATLAS obtained on 2025 August 6 (Epoch 1), 2025 December 22 (Epoch 2), and 2026 April 1 (Epoch 3), spanning…
Thermophysical characterization of the potentially hazardous near-Earth object 2024 YR4
T. G. Müller, E. M. MacLennan, A. Y. Burdanov +7
The asteroid 2024 YR4 is a potentially hazardous Apollo-type near-Earth object. Its highly eccentric orbit produces close Earth-Moon encounters roughly every 4 years. A collection…
Gemini and Apache Point Multi-band Optical Imaging Characterization of Fragmenting Long-period Comet C/2025 K1 (ATLAS)
Carl Ingebretsen, Bryce T. Bolin, Meredith A. MacGregor +8
We present results from multi-band g, r, and i, observations of C/2025 K1 (ATLAS) taken with the Gemini North 8.1-m/GMOS imager on 2025 December 6 and December 24, and u, g, r, i,…
JWST Spatial-Spectral Mapping of Green Comet C/2022 E3 (ZTF)
Stefanie N. Milam, Nathan X. Roth, Geronimo L. Villanueva +9
We report a survey of molecular emission from cometary volatiles using the James Webb Space Telescope (JWST) toward Oort cloud comet C/2022 E3 (ZTF) carried out on UT 2023 February…
JWST Observations of Asteroid 2024 YR4 Rule Out a 2032 Lunar Impact and Demonstrate a New Regime for Planetary Defense Follow-up
Julien de Wit, Andrew S. Rivkin, Marco Micheli +12
At the end of its discovery apparition, the 60 m near-Earth object 2024 YR4 was associated with a non-zero probability of lunar impact during its 2032 December 22 close appro…
Water D/H in 3I/ATLAS as a Probe of Formation Conditions in Another Planetary System
Luis E. Salazar Manzano, Teresa Paneque-Carreño, Martin A. Cordiner +17
Water reservoirs in the Solar System exhibit a deuterium enrichment that links back to the physical environment at the time of stellar birth. Gas-phase and ice-grain deuterium enri…
Isotopic Evidence for a Cold and Distant Origin of the Interstellar Object 3I/ATLAS
Martin Cordiner, Nathan X. Roth, Marco Micheli +16
Interstellar objects provide the only directly observable samples of icy planetesimals formed around other stars, and can therefore provide insight into the diversity of physical a…
Coma Physics of an Interstellar Object: JWST Spatial-Spectral Mapping of 3I/ATLAS
Nathan X. Roth, Martin A. Cordiner, Stefanie N. Milam +17
We report a survey of molecular emission from cometary volatiles using the James Webb Space Telescope (JWST) toward interstellar object 3I/ATLAS carried out on UT 2025 December 22…
An Enriched Methane D/H Ratio in the Interstellar Object 3I/ATLAS
Nathan X. Roth, Martin Cordiner, Stefanie Milam +15
Interstellar objects are interlopers from other planetary systems, and their volatile compositions provide a glimpse into planet formation around their host star. We present near-i…
Astrometric follow-up of near-Earth asteroid 2024 YR4 during a Torino scale level 3 alert
Marco Micheli, Maxime Devogèle, Larry Denneau +38
The discovery of 2024 YR4 presented the planetary defense community with the most significant impact threat in almost two decades, reaching level 3 on the Torino scale. The communi…
Catastrophic disruption of asteroid 2023 CX1 and implications for planetary defense
Auriane Egal, Denis Vida, François Colas +94
Mitigation of the threat from airbursting asteroids requires an understanding of the potential risk they pose for the ground. How asteroids release their kinetic energy in the atmo…
Space Mission Options for Reconnaissance and Mitigation of Asteroid 2024 YR4
Brent W. Barbee, Matthew A. Vavrina, Rylie Bull +17
Near-Earth asteroid 2024 YR4 was discovered on 2024-12-27 and its probability of Earth impact in December 2032 peaked at about 3% on 2025-02-18. Additional observations ruled out E…
JWST detection of a carbon dioxide dominated gas coma surrounding interstellar object 3I/ATLAS
Martin A. Cordiner, Nathaniel X. Roth, Michael S. P. Kelley +10
3I/ATLAS is the third confirmed interstellar object to visit our Solar System, and only the second to display a clear coma. Infrared spectroscopy with the James Webb Space Telescop…
Discovery and Preliminary Characterization of a Third Interstellar Object: 3I/ATLAS
Darryl Z. Seligman, Marco Micheli, Davide Farnocchia +44
We report initial observations aimed at the characterization of a third interstellar object. This object, 3I/ATLAS or C/2025 N1 (ATLAS), was discovered on 2025 July 1 UT and has an…
NSF-DOE Vera C. Rubin Observatory Observations of Interstellar Comet 3I/ATLAS (C/2025 N1)
Colin Orion Chandler, Pedro H. Bernardinelli, Mario Jurić +305
We report on the observation and measurement of astrometry, photometry, morphology, and activityof the interstellar object 3I/ATLAS, also designated C/2025 N1 (ATLAS) with the NSF-…
First JWST spectrum of distant activity in Long Period Comet C/2024 E1 (Wierzchos)
Colin Snodgrass, Carrie E. Holt, Michael S. P. Kelley +10
We observed the new Long Period Comet C/2024 E1 (Wierzchos), inbound at 7 au from the Sun, using the NIRSpec integral field unit on JWST. The spectrum shows absorption features due…
On The Lunar Origin of Near-Earth Asteroid 2024 PT5
Theodore Kareta, Oscar Fuentes-Muñoz, Nicholas Moskovitz +2
The Near-Earth Asteroid (NEA) 2024 PT5 is on an Earth-like orbit which remained in Earth's immediate vicinity for several months at the end of 2024. PT5's orbit is challenging to p…
Two Distinct Populations of Dark Comets Delineated by Orbits and Sizes
Darryl Z. Seligman, Davide Farnocchia, Marco Micheli +7
Small bodies are capable of delivering essential prerequisites for the development of life, such as volatiles and organics, to the terrestrial planets. For example, empirical evide…
Telescope-to-Fireball Characterization of Earth Impactor 2022 WJ1
Theodore Kareta, Denis Vida, Marco Micheli +10
Comparing how an asteroid appears in space to its ablation behavior during atmospheric passage and finally to the properties of associated meteorites represents the ultimate probe…
Strong Nongravitational Accelerations and the Potential for Misidentification of Near-Earth Objects
Aster G. Taylor, Darryl Z. Seligman, Matthew J. Holman +5
Nongravitational accelerations in the absence of observed activity have recently been identified on NEOs, opening the question of the prevalence of anisotropic mass-loss in the nea…
Debiasing astro-Photometric Observations with Corrections Using Statistics (DePhOCUS)
Tobias Hoffmann, Marco Micheli, Juan Luis Cano +5
Photometric measurements allow the determination of an asteroid's absolute magnitude, which often represents the sole means to infer its size. Photometric observations can be obtai…