The December 2025 Astronomy & Astrophysics (vol. 704) still says “in progress”, but January is already being trickled out. So I’m going to call it for December, and what a month:
Peña-Asensio, E. Seligman, D. Z. The interstellar flux gap: From dust to kilometer-scale objects L1 202557337
Wei, Z. Zhang, P. Zhang, H. et al. Reflectance-spectroscopic and polarization measurements of meteorite mixtures relevant to E- and M-type asteroids A20 202555612
Wimarsson, J. Ferrari, F. Jutzi, M. The diverse shapes of binary asteroid satellites born from sub-escape-velocity moonlet mergers A29 202555914
Hanuš, J. Delbo, M. Pokorný, P. et al. Physical characterization of asteroid (16583) Oersted combining stellar occultation and photometric data A67 202556313
Hui, M-T. Weryk, R. Deen, S. et al. Dynamically new comet C/2025 D1 (Groeller) with record perihelion distance A85 202557175
Gunell, H. Stenberg Wieser, G. Moeslinger, A. et al. Langmuir waves observed at comet 67P/Churyumov-Gerasimenko A115 202555043
Xin, Y. Skorov, Yu. Zhao, Y. et al. Modeling of comet water production – II. Dust layer removal model: The case of 67P/Churyumov-Gerasimenko A122 202555883
Guo, W. Cai, Z. Liu, B. et al. Orientation of the rotation axis and the location of water-ice sublimation activity of the main-belt comet 313P/Gibbs A124 202556433
Martin, M. Canu-Blot, R. Stenberg Wieser, G. et al. High charge-state solar wind ions interacting with comet 67P/Churyumov-Gerasimenko – Observations and comet activity estimates A160 202557620
Namouni, F. High-inclination Centaur reservoirs beyond Neptune A168 202556790
Waniak, W. Drahus, M. Component-resolved light curve of the binary main-belt comet 288P/2006 VW139 A169 202555856
San Sebastián, I. L. Klar, L. Jutzi, M. et al. Compressibility and strength of pebble piles A206 202556254
Vojáček, V. Borovička, J. Spurný, P. Spectroscopic analysis of hydrogen and silicon in bright fireballs: New insights into meteoroid composition A241 202556816
Kuksenko, V. Tóth, J. Population of the Oort cloud rocky meteoroids from the AMOS Meteor Network with implications for the Solar System cosmogony A243 202555020
Suer, T-A. Steenstra, E. S. Marchi, S. et al. The formation and structure of iron-dominated planetesimals A226 202554674
Zhang, X. Cui, L. Wei, X. et al. Asteroid-GS: 3D Gaussian splatting for fast surface reconstruction of asteroids A247 202556730
Stǎnescu, M. Popescu, M. M. Curelaru, L. et al. Data-parallel methods for fast and deep detection of asteroids on the Umbrella platform: Near-real-time synthetic tracking algorithm for nea… A13 202553973
We see interstellar dust, as collective clouds… we see interstellar objects, if they enter our System. But no interstellar boulders, <1 km. No news is good news? Peña-Asensio et al. read between the lines.
We can see S-type and C-type asteroids, distinguished by our spectroscopes. But the E-, M-, and P-types all blend together (“X-complex asteroids”). Or do they? Wei et al. attempt to add polarimetry data, trying to find the valuable M-type (“Metal”) asteroids.
Wei is joined by Suer et al., attempting to back-calculate the history of these metal asteroids.
Plenty of asteroids have asteroid satellites. The dynamics of asteroid splitting and satellite formation is a rich subfield. Wimarsson et al. do the dynamics calculations.
Besides spectra and polarization, we occasionally get occultations (little “eclipses”, where a small body passes in front of a background star). Hanuš et al. do one such field study.
Comet Groeller will never get closer to the Sun than Saturn’s orbit. Yet, the comet showed weak activity. What’s going on here? Hui et al. find supervolatiles- ices that melt before water.
The Rosetta mission didn’t unlock the secrets of comet activity, hence Xin et al. But it did study fields and particles (heliospherics) extensively, hence Gunell et al. and Martin et al.
The Main-Belt comets are peculiar beasts indeed. Asteroids, comets, or both? Neither? Guo et al. and Waniak et al. shed some light on these specimens.
Meanwhile, the Centaurs never get close enough to the Sun to activate and emit. For all we know, they could be comet nuclei that just stay in deep freeze. Namouni also tries to shed some light.
We spent twenty years calling some asteroids “rubble piles”, strengthless clumps held together with their self-gravity alone. Recently, it appears even rubble piles have weak (yet non-zero) strength. San Sebastián et al. consider the mechanics of small (and therefore dustless) rubble piles.
Meteors are fragments of comets and asteroids. Our nicer meteor camera arrays can give some sort of orbit for them before they had reached Earth. Vojáček et al., and Kuksenko et al., tackle meteors from both the beginning and ending approaches.
And now on to computer astronomy. Faster processors let us do things we could only imagine in the past. Zhang et al. tackle mapping of body surfaces, which we used to do by hand, assembling photos like badly-made tiles. Now we can have computers “wrap” digital images. On the sky in general, stacking two sky-search images can reveal fainter objects than the individual pictures. This lets us use smaller telescopes. With computers, we can stack multiple images to find fainter asteroids than ever before. Stǎnescu et al. have a new stacking algorithm, reducing processor requirements.