An Even More Precise View of Aluminum-26 in the Solar Nebula 26 Al might have come from: –Active stars before the Solar System formed, or –Radiation of dust near the young, active Sun Distinguishing between these choices requires precise measurements of Al and Mg isotopes to test whether 26 Al was distributed uniformly in the Solar System Uniform 26 Al distribution is also essential for its use as a chronometer Wolf-Rayet star spewing stellar winds

An Even More Precise View of Aluminum-26 in the Solar Nebula High-precision isotope data for 15 chondrules (example on left) shows that they all lie on a common growth line that assumes a uniform 26 Al/ 27 Al ratio of 5.2 x 10 -5, the value in calcium- aluminum-inclusions in primitive chondrites.

An Even More Precise View of Aluminum-26 in the Solar Nebula