EU-ESA Workshop on Meteor Observations for Planetary Defence

3 Nov 2026, 09:00 → 5 Nov 2026, 18:00 Europe/Amsterdam

Petralia Sottana, Sicily

Juan L. Cano (ESA), Maxime Devogele (ESA NEOCC), Richard Moissl, Francisco Ocaña, Thea Dethlefsen (European Commision)

Rational

Small imminent impactors are now routinely being detected before impact and allow the support of a new collaborative model for planetary defence. Most pre-impact cases to date are in the metre-range where we can combine pre-entry telescopic observations with atmospheric measurements from fireball networks, radar, infrasound, and space-based sensors. This end-to-end chain provides a unique testbed for linking orbit, entry behavior, and physical properties within a single event. Europe has strong capabilities across all these techniques, but the interfaces between communities remain fragmented. This workshop brings them together to build workflows from detection to characterisation to fireball analysis to combined interpretation, improving both near-term operational readiness and the scientific basis for assessing future impact threats. 

Workshop goals

• Map the end-to-end European workflow for imminent impactors: detection, rapid telescopic follow-up, atmospheric observation, and integrated post-event analysis. 
• Define coordination interfaces between communities to enable rapid multi-network response. 
• Establish how combined pre-impact and atmospheric datasets can constrain trajectory, physical properties, and impact effects for future planetary-defence readiness. 
• Build sustained communication channels between the astronomer/planetary-defence comunity and the meteor community, including regular cross-community exchanges, shared terminology, and clear points of contact for imminent-impact events. 

 

Tentative sessions:

• Radar observations
• All sky camera networks
• Infrasound and Seismics
• Other opportunistic sensors
• Trajectory reconstruction, Orbit determination, and Strewn fields
• Spectroscopy & Physical properties of fireballs 
• From meteorites to planetary defence

 

Privacy notice

Tuesday 3 November

09:00 → 10:20 Introduction to the workshop and planetary defence

10:20 → 10:50 Coffee break

10:50 → 12:30 Observation of meteors using radar techniques

Radar observations are the small-end of the meteor detections. Forward-scatter and multistatic systems detect particles form sub-millimetre dust to centimetre-scale meteors, continuously and regardless of daylight or cloud cover. Most European radar systems are optimised for this regime (i.e. shower monitoring and sporadic flux statistic). The PD-relevant question is what radar contributes at larger sizes, where it falls short, and where it hands off to the optical networks that follow.

12:30 → 14:00 Lunch

14:00 → 16:00 All-sky Camera Networks

Optical fireball networks occupy the central range of the size ladder: from centimetre-scale bright meteors up to the metre-class fireballs most relevant to planetary defence. This is the richest observational regime. Cameras record trajectory, light curve and spectra simultaneously, enabling orbit determination, composition estimates and physical characterisation.

16:00 → 16:30 Coffee break

16:30 → 18:00 Infrasound and seismic detection of meteors

Infrasound closes the size ladder at the large end. Signals from bolides of roughly 5m and above propagate through the atmosphere and are detectable at global distances by the IMS network's 60 stations. Infrasound is the only technique providing coverage over oceans and uninhabited regions where no optical or radar infrastructure will ever exist. Two tensions define this sessions: the detection threhold limits infrasounds to the large size object that rarely impact, and the IMS data which is controlled by CTBTO for nuclear monitoring is not fully open to the scientific community. Both deserve honest discussion.

Wednesday 4 November

09:05 → 10:35 Observation of meteor using opportunistic sensors and methods

Weather radar networks (EUMETNET OPERA's 200+ radars) were built for precipitation monitoring. Geostationary lightning imagers (GOES/GLM for the Americas, Meteosat MTG-LI for Europe and Africa) were built to map thunderstorms. Both detect meteors as an unexpected byproduct. Weather radar catches falling meteorite debris on the way down, providing strewn-field constraints in daytime or cloud cover. Lightning imagers detect the bolide light flash at hemisphere scale (over oceans, polar regions and uninhabited areas where no ground network will ever operate). Together they fill the coverage gaps that all previous sessions left open. The session also confronts a recurring tension: these sensors are controlled by meteorological agencies and space operators, not by the meteor community. Access to and scientific use of data systems you do not own is a challenge this community must address.

10:35 → 11:05 Coffee break

11:05 → 12:30 Trajectory Reconstruction, Orbit Determination & Strewn Field

The pre-atmospheric orbit links the fireball to its source population as a direct empirical connection to the NEO catalogue. The trajectory is also the starting point for dark flight modelling: prediction where meteorite fragments land, enabling field recovery campaigns. The Winchcombe meteorite (2021), recovered from a precise strewn field defined by UK fireball network data, is the archetype of what this pipeline produces at its best: a physically pristine sample with a known orbit, available for laboratory analysis.

12:30 → 18:00 Lunch and visit to Monte Mufara

Thursday 5 November

09:05 → 10:35 Spectroscopy & Physical Properties of Fireballs: Spectroscopy and physical properties of Fireballs

Spectroscopy is the only technique that provides direct elemental composition measurements of small impactors in flight. Combined with light-curve photometry, it constrains bulk density, tensile strength, ablation coefficient and fragmentation behaviour: the physical parameters that determine whether an object produces a harmless fireball, a meteorite fall, or an airburst with ground damage. These are also the parameters that the impact modelling community needs most urgently has the least reliable data for. The link to NEO taxonomy closes the loop to the telescopic survey: Given a spectral class, what do fireball statistics tell us about the likely composition of the broader NEO population?

10:35 → 11:05 Coffee break

11:05 → 12:30 From meteor observations to planetary defence

The empirical flux derived from European fireball networks, corrected for detection efficiency and combined with space-based bolide catalogues, is the most direct measurement we have of the impact of the hazard in the 1-5m range. Where do fireball-derived size-frequency distributions agree with theoritical models, and where do they diverge? What does this mean for risk thresholds, alert criteria and ESA/EC planetary defence planning?

12:30 → 14:00 Lunch

14:00 → 15:30 Open discussions and final thoughts

15:30 → 16:00 Coffee break

16:00 → 17:00 Open discussions and final thoughts