Upcoming SwRI Boulder Colloquia

Colloquia are normally on Tuesdays at 11:00 am in the 4th-floor conference room, except as indicated below in bold text.
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For questions or suggestions for speakers, please contact the SwRI colloquium organizers:
Raluca Rufu, 303-226-0879 or raluca(at)boulder.swri.edu
Julien Salmon, 720-208-7203 or julien(at)boulder.swri.edu
Kelsi Singer, 303-226-5910 or ksinger(at)boulder.swri.edu
Sierra Ferguson, sierra.ferguson(at)swri.org
Rogerio Deienno, rogerio.deienno(at)swri.org
Sam Van Kooten, 303-226-5909 or svankooten(at)boulder.swri.edu

To be added to the SwRI Boulder Colloquia email list, please contact Kelsi Singer, ksinger(at)boulder.swri.edu

Suggest a New Speaker HERE

Tue Jun 3, 2025 11:00 am Ian Wong Space Telescope Science Institute (STScI) The unique surface and outgassing of the distantly active Centaur Chiron as revealed by JWST observations

Abstract: Centaurs are inward-scattered objects from the Kuiper belt that orbit within the giant planet region. Their closer heliocentric distances compared to Kuiper belt objects enable more detailed explorations of the surface properties of outer solar system bodies. Meanwhile, the higher levels of irradiation provide a unique window into the effects of thermal processing on the surface properties of icy planetesimals. Chiron is one of the largest Centaurs, with an effective diameter of 210 km. Notably, Chiron belongs to the enigmatic subpopulation of active Centaurs and has displayed cometary activity several times since its discovery. In March 2021, Chiron underwent an outburst while it was at a heliocentric distance of 18.8 AU. This report of Centaur activity is the most distant to date by a significant margin and challenges our prevailing understanding of the mechanisms that trigger and sustain outgassing on these objects. A holistic picture of Chiron's surface and coma promises to revolutionize our understanding of Centaur activity and the properties of primitive icy planetesimals near and far. In January 2024, we obtained observations of Chiron with the Near Infrared Spectrograph on JWST as part of Cycle 2 Director's Discretionary Time (DDT) Program 4621 (PI: Ian Wong), following up on earlier spectra from Cycle 1 Guaranteed Time Observation (GTO) Program 1273 (PI: Jonathan Lunine). The spectra span 1.7 – 5.1 microns and reveal a wide range of surface ices, with CO2 displaying exceptionally deep absorption features when compared to other similarly-sized minor bodies. The higher spectral resolution of the DDT observations resolves the individual emission bands of outgassed CO2 and CH4 and enables detailed modeling of the fluorescence signatures, yielding well-constrained production rates of both molecules. From the spatial information provided by the integral field unit, we are able to map the distribution of the gaseous constituents within the coma. In this talk, I will present the results of our DDT observations of Chiron, place Chiron within the context of other active bodies observed with JWST, and discuss the broader implications for our understanding of distant cometary activity and the formation and evolution of icy planetesimals throughout the Solar System.

Thu Jun 12, 2025 11:00 am Rakesh Mogul California State Polytechnic University Water, iron sulfate, and sulfuric acid are major components in Venus’ aerosols

Tue Jun 17, 2025
In Room 4.615 11:00 am Juan Lora Yale University TBD

Tue Jun 24, 2025 11:00 am Prachi Chavan Diego Portales University From Disks to Comets: A Multi-frequency Study of Dust from Ophiuchus Molecular Cloud to the Oort Cloud

Tue Jul 22, 2025
In Room 4.615 11:00 am Rutu Parekh Jet Propulsion Laboratory TBD

Tue Aug 12, 2025
In Room 4.615 11:00 am Antonio F. Bertachini A. Prado Instituto Nacional de Pesquisas Espaciais - INPE TBD

Tue Aug 19, 2025
In Room 4.615 11:00 am Erin Leonard JPL TBD

Tue Jun 3, 2025	11:00 am	Ian Wong	Space Telescope Science Institute (STScI)	The unique surface and outgassing of the distantly active Centaur Chiron as revealed by JWST observations
	Abstract:	Centaurs are inward-scattered objects from the Kuiper belt that orbit within the giant planet region. Their closer heliocentric distances compared to Kuiper belt objects enable more detailed explorations of the surface properties of outer solar system bodies. Meanwhile, the higher levels of irradiation provide a unique window into the effects of thermal processing on the surface properties of icy planetesimals. Chiron is one of the largest Centaurs, with an effective diameter of 210 km. Notably, Chiron belongs to the enigmatic subpopulation of active Centaurs and has displayed cometary activity several times since its discovery. In March 2021, Chiron underwent an outburst while it was at a heliocentric distance of 18.8 AU. This report of Centaur activity is the most distant to date by a significant margin and challenges our prevailing understanding of the mechanisms that trigger and sustain outgassing on these objects. A holistic picture of Chiron's surface and coma promises to revolutionize our understanding of Centaur activity and the properties of primitive icy planetesimals near and far. In January 2024, we obtained observations of Chiron with the Near Infrared Spectrograph on JWST as part of Cycle 2 Director's Discretionary Time (DDT) Program 4621 (PI: Ian Wong), following up on earlier spectra from Cycle 1 Guaranteed Time Observation (GTO) Program 1273 (PI: Jonathan Lunine). The spectra span 1.7 – 5.1 microns and reveal a wide range of surface ices, with CO2 displaying exceptionally deep absorption features when compared to other similarly-sized minor bodies. The higher spectral resolution of the DDT observations resolves the individual emission bands of outgassed CO2 and CH4 and enables detailed modeling of the fluorescence signatures, yielding well-constrained production rates of both molecules. From the spatial information provided by the integral field unit, we are able to map the distribution of the gaseous constituents within the coma. In this talk, I will present the results of our DDT observations of Chiron, place Chiron within the context of other active bodies observed with JWST, and discuss the broader implications for our understanding of distant cometary activity and the formation and evolution of icy planetesimals throughout the Solar System.
Thu Jun 12, 2025	11:00 am	Rakesh Mogul	California State Polytechnic University	Water, iron sulfate, and sulfuric acid are major components in Venus’ aerosols
Tue Jun 17, 2025 In Room 4.615	11:00 am	Juan Lora	Yale University	TBD
Tue Jun 24, 2025	11:00 am	Prachi Chavan	Diego Portales University	From Disks to Comets: A Multi-frequency Study of Dust from Ophiuchus Molecular Cloud to the Oort Cloud
Tue Jul 22, 2025 In Room 4.615	11:00 am	Rutu Parekh	Jet Propulsion Laboratory	TBD
Tue Aug 12, 2025 In Room 4.615	11:00 am	Antonio F. Bertachini A. Prado	Instituto Nacional de Pesquisas Espaciais - INPE	TBD
Tue Aug 19, 2025 In Room 4.615	11:00 am	Erin Leonard	JPL	TBD