If not issues, Planetary Science Journal has unambiguous volumes. In the new vol. 6, we start with some interesting papers for a first installment:
Hsieh, H. H. et al. The Volatile Composition and Activity Evolution of Main-belt Comet 358P/PANSTARRS art. 3 ad9199
Simon, A. A. et al. Lucy L’Ralph In-flight Calibration and Results at (152830) Dinkinesh
art. 7 ad9921
Rivkin, A. S. et al. Observations and Quantitative Compositional Analysis of Ceres, Pallas, and Hygiea Using JWST/NIRSpec art 9 ad944c
Wilkins, O. H. et al. Photolysis and Sublimation Chemistry of Ammonium Cyanide with
Relevance to Cometary Environments art 10 ad9a67
Jewitt, D. Nongravitational Forces in Planetary Systems art 12 ad9824
Main-Belt Comets: is there any grayer boundary line in this Solar System? (134340) Pluto isn’t palpably shedding into a tail, nor is it at a lone size point (Eris is, to first order, same). But the MBCs fail so many ‘comethood’ criteria, other than a tail, that any data one might take (after Main-Belt-hood, already known) is new territory. Before, the one MBC with known volatile composition was observed by JWST, due to the low activity and very faint coma. Tracking the progression of activity also eliminates impact per se as its cause.
Lucy is flying fine, with the L’Ralph instrument. It’s a rebuild of the Ralph on New Horizons, itself a rebuild of one on EO-1 (Earth Observing-1), a prototype for lightweight weather/climate sats. Despite the recurrences, each of the builds ran with an assumption of no more units, and was de facto a custom job. There is thus no use of process control or statistical methods to verify/validate a unit. No, we test L’Ralph the same way as a unique build, by testing it in flight on known targets. Here, now is the L’Ralph test data.
As above, JWST has sensitivity, from a large aperture and no pesky air in the way. This is minor in visible light, but a bigger and bigger deal as one goes to longer wavelengths. Wavelengths like 2.6-6 microns are diagnostic, as they contain many molecules that are in question at the small bodies. Does the ability to view at a few microns tell us of small-body compositions? There’s only one way to find out, is there: apply for JWST time, and see. See about any possible volatile compositions, on questionable bodies.
One of those volatile molecule(s) is nitrile and variants. Nitrogen is not rare, just hard to pin down on many levels. The combination of N and other common elements (C, O, and H- heteroatoms) in particular has implications for further reactions and life. Grasping NHx and CN chemistry in relevant conditions (like dusts and frosts) might point (again) to small bodies as the bringers of life- if not true panspermia, something close. Or who knows- maybe something else we can’t even predict just yet.
Finally, let’s not ignore end result. Comets (including Main-Belt ones) emit, and emission can actually blow a body around. Before exhaustion (many thousands of years), a comet may actually change populations, ending in another zone of the Solar System. Such “nongravitational force” is thus of more than historical interest, for this System and others. It’s clearly worth a paper, and comet expert (including MBCs) David Jewitt is clearly worthy of writing that paper.