McCoy T J, Russell S S, Zega T J, Thomas-Keprta K L, Singerling S A, Brenker F E, Timms N E, Rickard W D A, Barnes J J, Libourel G, Ray S, Corrigan C M, Haenecour P, Gainsforth Z, Dominguez G, King A J, Keller L P, Thompson M S, Sandford S A, Jones R H, Yurimoto H, Righter K, Eckley S A, Bland P A, Marcus M A, DellaGiustina D N, Ireland T R, Almeida N V, Harrison C S, Bates H C, Schofield P F, Seifert L B, Sakamoto N, Kawasaki N, Jourdan F, Reddy S M, Saxey D W, Ong I J, Prince B S, Ishimaru K, Smith L R, Benner M C, Kerrison N A, Portail M, Guigoz V, Zanetta P-M, Wardell L R, Gooding T, Rose T R, Salge T, Le L, Tu V M, Zeszut Z, Mayers C, Sun X, Hill D H, Lunning N G, Hamilton V E, Glavin D P, Dworkin J P, Kaplan H H, Franchi I A, Tait K T, Tachibana S, Connolly H C, Lauretta D S
Department of Mineral Sciences, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.
Planetary Materials Group, Natural History Museum, London, UK.
Nature. 2025 Jan;637(8048):1072-1077. doi: 10.1038/s41586-024-08495-6. Epub 2025 Jan 29.
Evaporation or freezing of water-rich fluids with dilute concentrations of dissolved salts can produce brines, as observed in closed basins on Earth and detected by remote sensing on icy bodies in the outer Solar System. The mineralogical evolution of these brines is well understood in regard to terrestrial environments, but poorly constrained for extraterrestrial systems owing to a lack of direct sampling. Here we report the occurrence of salt minerals in samples of the asteroid (101955) Bennu returned by the OSIRIS-REx mission. These include sodium-bearing phosphates and sodium-rich carbonates, sulfates, chlorides and fluorides formed during evaporation of a late-stage brine that existed early in the history of Bennu's parent body. Discovery of diverse salts would not be possible without mission sample return and careful curation and storage, because these decompose with prolonged exposure to Earth's atmosphere. Similar brines probably still occur in the interior of icy bodies Ceres and Enceladus, as indicated by spectra or measurement of sodium carbonate on the surface or in plumes.
富含溶解盐的稀浓度富水流体蒸发或冻结会产生卤水，这在地球上的封闭盆地中可以观察到，并且通过对太阳系外层冰体的遥感探测也能发现。这些卤水的矿物演化在地球环境方面已得到很好的理解，但由于缺乏直接采样，对外星系统的限制很大。在这里，我们报告了由奥西里斯-雷克斯任务带回的小行星（101955）贝努样本中盐矿物的存在情况。这些盐矿物包括含钠磷酸盐以及在贝努母体历史早期存在的晚期卤水蒸发过程中形成的富钠碳酸盐、硫酸盐、氯化物和氟化物。如果没有任务样本返回以及精心的保存和存储，就不可能发现多种盐类，因为这些盐类在长时间暴露于地球大气中会分解。谷神星和土卫二这两颗冰体内部可能仍然存在类似的卤水，这从它们表面或羽流中碳酸钠的光谱或测量结果可以看出。
