8 papers
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…
The ESA Meerkat Asteroid Guard: a monitoring service for imminent impactors
Charlie Drury, Francesco Gianotto, Marco Fenucci +9
We present the Meerkat Asteroid Guard, an imminent impactor warning service developed and maintained by the European Space Agency's Near-Earth Object Coordination Centre (NEOCC). T…
Rapid-response characterization of near-Earth asteroid 2024 YR4 during a Torino Scale 3 alert
Maxime Devogèle, Olivier R. Hainaut, Marco Micheli +32
On 27 December 2024, near-Earth object (NEO) 2024 YR was discovered by the ATLAS survey and identified as a virtual impactor. A few weeks later, it eventually reached level 3 o…
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…
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…
Astrometry, orbit determination, and thermal inertia of the Tianwen-2 target asteroid (469219) Kamo`oalewa
Marco Fenucci, Bojan NovakoviÄ, Pengfei Zhang +9
Context. (469219) Kamo`oalewa is a small near-Earth asteroid, which is currently a quasi-satellite of the Earth. Lightcurve measurements also reveal a rotation period of only about…