Centaur Exploration Workshop 2019 and its Deliverables: The
Roots of Activity
Gal Sarid (1), Maria Womack (1) and the participants of the
CEW2019 Workshop, Florida Space Institute, University of Central
Florida, Orlando, Florida, USA ([email protected])
Abstract We present here the rationale, content and outcomes of
a unique workshop, which addressed the scientific importance and
space exploration relevance of active centaurs. It was specifically
focused on mapping knowledge gaps and paths forward. The 2019
Cen-taur Exploration Workshop (CEW2019) was an in-ternational and
diverse meeting with clear deliver-ables to compile a summary
“white paper” about all physical and observational aspects of
activity in the outer solar system, as well as converge on a
multi-wavelength long-term observation plan.
1. Introduction Centaurs are minor bodies whose orbits are in
transi-tion between the Kuiper Belt and inner solar system and
strongly interact with the giant planets [1]. Many of these show
activity, including explosive outbursts well beyond the water-ice
sublimation zone, reveal-ing clues to their nucleus’ composition,
structure and history [2, 3]. Thus, Centaurs play a unique role in
testing models of solar system formation and evolu-tion, and there
is a rapidly increasing appetite by scientists to discuss results
and make plans for this changing field. Centaur Exploration
Workshop 2019: The Roots of Activity (CEW2019) is the third in a
series of meetings devoted to Centaurs, which ran 2.5 days in March
2019 with 60+ attendees. It was held in at the University of
Central Florida, under the auspices of the Florida Space Institute,
the Center for Lunar and Asteroid Surface Science and SSERVI
Central. The workshop’s impetus (see Table 1) was two-fold:
Advancing our understanding of how small bodies originate, evolve
and become active beyond Jupiter’s orbit; Plan exploration
strategies with re-mote observations of representative Centaurs.
The former served as our science rationale, while the latter helped
focus our discussions and deliverables on future remote and in-situ
characterization of spe-
cific targets. The organizers strongly encouraged the
participation of early career researchers and offered two modes of
participation: Half of the attendees were in Orlando and the other
half joined in with remote login. Contributions were solicited on
the following perceived knowledge gaps:
• Structure: Strength, Density, Porosity, Shape ef-fects,
Sub-surface layering.
• Composition: Dust properties, Volatile abun-dances, Coma
speciation, Noble gases.
• Dynamics: Rotation state, Orbit uniqueness, Or-bital history
and lifetime, Rings, Secondaries.
• Activity: Quiescent, Outbursts, Dust-Gas correla-tion, Jet
shape, Solar wind interaction.
The schedule contained overview talks, forward-looking
presentation, and guided discussions. The last half day was
dedicated to exploring the action items of individual talks from
the first two days, and creating a list of targeted questions and
tasks, which will lead to the final two workshop deliverables: A
White Paper (state-of-the-art, prioritized knowledge gaps,
characterization and exploration pathways of Centaurs) and
Observing Campaign.
Table 1: CEW2019 Workshop summary Goals Understand behaviour,
origin and evo-
lution; Preliminary concept design for exploration strategy
Deliverables Concept design, map needs and meth-ods, summarize
SKGs and importance of target selection, white paper and
coordinated observing plans, and pub-licly accessible meeting
playback.
Format Allow streaming of ideas and planning, encourage
participation from junior contributors.
Participation High-level discussion and global com-munity
participation.
EPSC AbstractsVol. 13, EPSC-DPS2019-859-1, 2019EPSC-DPS Joint
Meeting 2019c© Author(s) 2019. CC Attribution 4.0 license.
2. Relevance The workshop’s main purpose was to facilitate a
comprehensive and inter-disciplinary analysis of Centaurs, and to
help lay the groundwork for the preliminary concept design of an
exploration effort (mission). Thus, CEW2019 was very timely and
played well into stated objectives/goals of the NASA SMD and NSF
AST Division. The theme of the workshop, its stated goals and
deliverables (Table 1) are also within the scope of the NRC
Planetary Sci-ence Decadal Survey (e.g., a Centaur mission con-cept
study). The exploration of Centaur objects, spe-cifically active
ones, is also included in recommenda-tions for future exploration
within the Discovery and New Frontiers class missions. This work is
also sup-ported by a plan for a comprehensive observing cam-paign
using both ground- and space-based assets.
3. Deliverables A first draft of the White Paper is underway,
with sections distributed amongst different sub-groups, composed of
workshop participants (both local and remote). An archived website
with playback of the workshop presentations and discussions is
available at: https://cew2019.arc.nasa.gov An observing cam-paign
is also being crafted by participants and is planned to have
world-wide involvement of astrono-mers with a variety of techniques
using both ground-based and space-based telescopes.
Figure 1: A panorama of some of the “in situ”
(sit-ting/standing) and “remote” (on the screen) partici-pants of
the CEW2019 workshop.
Figure 2: Greeting page for the CEW2019 website, which contains
recordings of the presentations and discussions.
https://cew2019.arc.nasa.gov
Acknowledgements We acknowledge the support of CLASS at UCF, FSI
support staff, SSERVI technical support staff and the following
individuals: Zoe Landsman (LOC & logis-tics), Cody Schultz (A/V
& local technical support), Jennifer Larson (Logistics), Olga
Harrington Pinto (Logistics), SOC members – Kelsi Singer, Henry
Hsieh, Yan Fernandez. MW and GS also acknowl-edge support from NSF
AST-1615917.
References [1] Gladman, B. Marsden, B.G., and Van Laerhoven, C.
Nomenclature in the Outer Solar System, 43-57, 2008.
[2] Jewitt, D. The Active Centaurs, AJ, 137(5):4296-4312,
2009.
[3] Wierzchos, K., Womack, M., Sarid, G., AJ, 153(5):230,
2017.
