Igneous meteorites suggest Aluminium-26 heterogeneity in the early Solar NebulaOPEN ACCESS 

Evgenii Krestianinov, Yuri Amelin, Qing-Zhu Yin, Paige Cary, Magdalena H. Huyskens, Audrey Miller, Supratim Dey, Yuki Hibiya, Haolan Tang, Edward D. Young, Andreas Pack & Tommaso Di Rocco

Nature Communications, Volume 14, Article number: 4940


“The short-lived radionuclide aluminium-26 (26Al) isotope is a major heat source for early planetary melting. The aluminium-26 – magnesium-26 (26Al-26Mg) decay system also serves as a high-resolution relative chronometer. In both cases, however, it is critical to establish whether 26Al was homogeneously or heterogeneously distributed throughout the solar nebula. Here we report a precise lead-207 – lead-206 (207Pb-206Pb) isotopic age of 4565.56 ± 0.12 million years (Ma) for the andesitic achondrite Erg Chech 002. Our analysis, in conjunction with published 26Al-26Mg data, reveals that the initial 26Al/27Al in the source material of this achondrite was notably higher than in various other well-preserved and precisely dated achondrites. Here we demonstrate that the current data clearly indicate spatial heterogeneity of 26Al by a factor of 3-4 in the precursor molecular cloud or the protoplanetary disk of the Solar System, likely associated with the late infall of stellar materials with freshly synthesized radionuclides.”