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arXiv · 0903.0237

The lost siblings of the Sun

S. Portegies Zwart
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Abstract

The anomalous chemical abundances and the structure of the Edgewood-Kuiper belt observed in the solar system constrain the initial mass and radius of the star cluster in which the sun was born to $M\simeq500$ to 3000 \msun and $R\simeq 1$ to 3 pc. When the cluster dissolved the siblings of the sun dispersed through the galaxy, but they remained on a similar orbit around the Galactic center. Today these stars hide among the field stars, but 10 to 60 of them are still present within a distance of $\sim 100$ pc. These siblings of the sun can be identified by accurate measurements of their chemical abundances, positions and their velocities. Finding even a few will strongly constrain the parameters of the parental star cluster and the location in the Galaxy where we were born.

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S. Portegies Zwart. 2009-03-02. The lost siblings of the Sun. https://doi.org/10.1088/0004-637x%2F696%2F1%2Fl13

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