In this “month’s” three issues of MNRAS (Monthly Notices, Roy. Astron. Society):
Volume 537, Issue 3, March 2025
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Volume 537, Issue 4, March 2025
Müller, D. R. Altwegg, K. Berthelieret, J-J. et al. Land of gas and dust – exploring bursting cavities on comet 67P Pages 2997 staf180
McGraw, A. Reddy, V. Sanchez, J. A. et al. The Gefion Asteroid Family: parent body puzzles and ordinary chondrite pieces Pages 3145 staf061
Volume 538, Issue 1, March 2025
Pranshu, K. Misra K. Ailawadhi, B. et al. PyLMT: a transient detection pipeline for the 4-m International Liquid Mirror Telescope Pages 133 staf206
Zhou, Y. F. Li, Z. Li, H. et al. Prediction for close approaches with terrestrial planets of asteroids from the main belt Pages 258 staf311
Gritsevich, M. Wesołowski, M. Castro-Tirado, A. J. Mass of particles released by comet 12P/Pons–Brooks during 2023–2024 outbursts Pages 470 staf219
Activity in general (loss of matter)- and dust studies in particular- was one of the mission requirements of ESA’s Rosetta probe. Unfortunately, ten years later, we still don’t have much of an understanding of how and why comet activity begins and continues. Researchers on, allied with, and not on the Rosetta team continue, including Müller et al. and, via other comets, Gritsevich et al. For one, there is both fallback (dust which fails to escape the comet’s gravity, and lands on the nucleus again) and hyperactivity (clumps which are shed from the nucleus, and in turn break apart themselves). How and why?
Asteroids, too, lose mass, but explicitly via collisions. These form asteroid families: swarms of asteroids in similar orbits, all flying gently away from their originating collision. One such family is the Gefion family. Is Ceres the parent (the original body which split into the family members), or is Gefion the parent, and Ceres is just an interloper in that part of the Main Belt? And do family members reach all the way down to meteorites which have reached all the way to Earth, and been collected?
In a pure coincidence, Zhou et al. have a related line of research. What dynamics cause material to reach Earth (or Mars, Venus, etc.) from the Main Belt? We have established that pieces of Vesta can reach Earth, via perturbations, and via resonances with the major planets’ gravity. Can we keep going for other Main Belt objects?
Finally, some mechanics under the hood. The 6-meter Canadian Large Zenith Telescope is dead, but we now have the 4-meter ILMT (International Liquid Mirror Telescope). Liquid telescopes can’t be pointed across the sky, making them lousy for survey work, but given their low cost, why not try anyway. Such is the case with the ILMT. In this case, the 4-meter aperture is no 6m, but still not to be brushed off. More specifically, asteroids and other sudden phenomena will, by chance, appear in the limited field of view. It is up to us to recognize them, and parse the images of them from the general ‘movie’ of the sky above the liquid telescope. Pranshu et al. go over the image parsing algorithm to do so.