Good Acta Astronautica for Feb (vol. 239):
Buys, M. Hanner, C. Refining asteroid mass uncertainty via volume, and bulk density constraints for optimal flyby mission design Pages 89 .2025.10.070
Bull, R. Vavrina, M. A. Lyzhoft, J. et al. Retaking in-flight spacecraft for rapid response reconnaissance in planetary defense exercises Pages 184 .2025.11.001
Bull, R. McMahon, J. Flyby asteroid mass measurement via optical tracking of kinetic impact debris Pages 194 .2025.10.041
Albrecht, R. Camacho-Lara, S. Jamschon Mac Garry, L. Geopolitical, socio-economic and legal aspects of the 2024PDC25 event Pages 307 .2025.10.069
Koeberl, C. Albrecht, R. Koudelka, O. et al. Multi-parameter monitoring of the potential impact of the exercise asteroid 2024 PDC25 Pages 563 .2025.11.012
Lang, A. Qin, Z. Liu, X. Uncertainty propagation of spacecraft orbits around asteroid 99942 Apophis using a hybrid MGMM-UT approach Pages 807 .2025.11.030
Characterization of asteroids is necessary- very necessary. Simply detecting them with a telescope (as a dot of light), then tracking them (i. e., orbit determination) merely tells us there’s a dot of light there. And, potentially, that dot of light may be coming our way. Buys et al., and Bull and McMahon, tackle this characterization: turning a dot of light into a place. Bull Vavrina et al. also do this, but from more of an engineering standpoint: how might we use spacecraft already in space, saving many months to a few years of project schedule?
And speaking of project, the PDCs (Planetary Defense Conferences) always include a tabletop asteroid exercise. The point of these is to shake out flaws in the system, and (eventually) improve our response should we actually find that one, unlucky asteroid. Albrecht et al. and Koeberl et al. are about that shakeout and improvement. On the day of crisis, we don’t want to be learning how.
One such ‘unlucky’ asteroid is Apophis. For a while, it looked like it might be an Earth threat. Now we know it will just barely miss us, cosmically speaking. But we are still sending RAMSES, OSIRIS-APEX, etc. to take advantage of the opportunity. Lang et al. try to make those missions improved.