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The consequences of a nearby supernova on the early Solar System

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 نشر من قبل Simon Portegies Zwart
 تاريخ النشر 2018
  مجال البحث فيزياء
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If the Sun was born in a relatively compact open cluster, it is quite likely that a massive (10MSun) star was nearby when it exploded in a supernova. The repercussions of a supernova can be rather profound, and the current Solar System may still bear the memory of this traumatic event. The truncation of the Kuiper belt and the tilt of the ecliptic plane with respect to the Suns rotation axis could be such signatures. We simulated the effect of a nearby supernova on the young Solar System using the Astronomical Multipurpose Software Environment. Our calculations are realized in two subsequent steps in which we study the effect of the supernova irradiation on the circumstellar disk and the effect of the impact of the nuclear blast-wave which arrives a few decades later. We find that the blastwave of our adopted supernova exploding at a distance of $0.15$--$0.40$,pc and at an angle of $35^circ$--$65^circ$ with respect to the angular-momentum axis of the circumsolar disk would induce a misalignment between the Suns equator and its disk to $5^circ.6pm1^circ.2$, consistent with the current value. The blast of a supernova truncates the disk at a radius between $42$ and $55$,au, which is consistent with the current edge of the Kuiper belt. For the most favored parameters, the irradiation by the supernova as well as the blast wave heat the majority of the disk to $sim 1200$,K, which is sufficiently hot to melt chondrules in the circumstellar disk. The majority of planetary system may have been affected by a nearby supernova, some of its repercussions, such as truncation and tilting of the disk, may still be visible in their current planetary systems topology. The amount of material from the supernova blast wave that is accreted by the circumstellar disk is too small by several orders of magnitude to explain the current abundance of the short live radionuclide $^{26}$Al.



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