Borucki W J, McKay C P
NASA Ames Research Center, Moffett Field, California 94035, USA.
Nature. 1987 Aug 6;328:509-10. doi: 10.1038/328509a0.
Spacecraft observations show that the presence of lightning activity is not confined to the terrestrial atmosphere, but is also found in the atmospheres of Venus, Jupiter and Saturn. Lightning activity may also occur in Titan's thick atmosphere. Calculations show that lightning produces a significant fraction of the nitric oxide that reacts with the ozone and chlorine compounds in the terrestrial stratosphere. In the atmosphere of the primordial Earth, lightning could have been the major source of many of the molecules required for the formation of life. To determine the effects of lightning activity in the atmospheres of other planets from spacecraft images requires a knowledge of the optical properties of the lightning discharge. Here we report the first simulations of lightning in planetary atmospheres by laser-induced plasmas. These simulations show that the fraction of the energy in lightning discharge channels that is radiated in the visible spectrum is similar for Earth, Venus and Titan, but quite different for Jupiter. One implication of our results is that the amount of trace gases produced by lightning in the jovian atmosphere must be larger than previously estimated.
航天器观测表明，闪电活动并非仅存在于地球大气层，在金星、木星和土星的大气层中也能发现。泰坦浓厚的大气层中可能也会发生闪电活动。计算表明，闪电产生的一氧化氮在与地球平流层中的臭氧和氯化合物发生反应的一氧化氮中占了很大一部分。在原始地球的大气层中，闪电可能是生命形成所需的许多分子的主要来源。要从航天器图像确定闪电活动对其他行星大气层的影响，需要了解闪电放电的光学特性。在此，我们报告首次通过激光诱导等离子体对行星大气层中的闪电进行的模拟。这些模拟表明，地球、金星和泰坦的闪电放电通道中在可见光谱中辐射的能量比例相似，但木星的情况则大不相同。我们的研究结果表明，木星大气层中闪电产生的痕量气体数量必定比之前估计的要多。
