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Arrhenius Reconsidered: Astrophysical Jets and the Spread of Spores

机译:重新考虑了阿累尼乌斯:天体物理射流和孢子传播

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In 1871, Lord Kelvin suggested that the fossil record could be an account of bacterial arrivals on comets. In 1903, Svante Arrhenius suggested that spores could be transported on stellar winds without comets. In 1984, Sir Fred Hoyle claimed to see the infrared signature of vast clouds of dried bacteria and diatoms. In 2012, the Polonnaruwa carbonaceous chondrite revealed fossilized diatoms apparently living on a comet. However, Arrhenius' spores were thought to perish in the long transit between stars. Those calculations, however, assume that maximum velocities are limited by solar winds to ~5 km/s. Herbig-Haro objects and T-Tauri stars, however, are young stars with jets of several 100 km/s that might provide the necessary propulsion. The central engine of bipolar astrophysical jets is not presently understood, but we argue it is a kinetic plasma instability of a charged central magnetic body. We show how to make a bipolar jet in a belljar. The instability is non-linear, and thus very robust to scaling laws that map from microquasars to active galactic nuclei. We scale up to stellar sizes and recalculate the viability/transit-time for spores carried by supersonic jets, to show the viability of the Arrhenius mechanism.
机译:1871年,开尔文勋爵(Lord Kelvin)建议说化石记录可能是彗星细菌到达的原因。 1903年,斯万特·阿伦尼乌斯(Svante Arrhenius)提出,可以在没有彗星的恒星风中运输孢子。 1984年,弗雷德·霍伊尔爵士声称看到了干燥细菌和硅藻的巨大云团的红外特征。 2012年,Polonnaruwa碳质球粒陨石显示化石硅藻显然生活在彗星上。但是,人们认为阿累尼乌斯的孢子在恒星之间的长途穿越中会灭亡。但是,这些计算假定最大速度被太阳风限制在〜5 km / s。但是,Herbig-Haro物体和T-Tauri恒星是年轻的恒星,其喷射速度为几百公里/秒,可能会提供必要的推进力。目前尚不了解双极天体物理射流的中心引擎,但我们认为这是带电的中心磁性体的动力学等离子体不稳定性。我们展示了如何在钟罩中制造双极射流。这种不稳定性是非线性的,因此对于缩放从微类星体到活跃银河核的定律非常稳健。我们按比例扩大到恒星大小,并重新计算超音速喷射器携带的孢子的生存力/传播时间,以显示Arrhenius机制的生存力。

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