Impacts are critical to producing the aqueous environments necessary to stimulate prebiotic chemistry on Titan’s surface. Furthermore, organic hazes resting on the surface are a likely feedstock of biomolecules. In this work, we conduct impact experiments on laboratory-produced organic haze particles and haze/sand mixtures and analyze these samples for life’s building blocks. Samples of unshocked haze and sand particles are also analyzed to determine the change in biomolecule concentrations and distributions from shocking. Across all samples, we detect seven nucleobases, nine proteinogenic amino acids, and five other biomolecules (e.g., urea) using a blank subtraction procedure to eliminate signals due to contamination. We find that shock pressures of 13 GPa variably degrade nucleobases, amino acids, and a few other organics in haze particles and haze/sand mixtures; however, certain individual biomolecules become enriched or are even produced from these events. Xanthine, threonine, and aspartic acid are enriched or produced in impact experiments containing sand, suggesting these minerals may catalyze the production of these biomolecules. On the other hand, thymine and isoleucine/norleucine are enriched or produced in haze samples containing no sand, suggesting catalytic grains are not necessary for all impact shock syntheses. Uracil, glycine, proline, cysteine, and tyrosine are the most unstable to impact-related processing. These experiments suggest that impacts alter biomolecule distributions on Titan’s surface, and that organic hazes co-occurring with fine-grained material on the surface may provide an initial source for further prebiotic chemistry on Titan.

中文翻译：

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泰坦上的生命起源化学：有机雾霾颗粒的撞击实验

撞击对于在土卫六表面产生刺激益生元化学所需的水环境至关重要。此外，表面的有机雾气可能是生物分子的原料。在这项工作中，我们对实验室生产的有机雾霾颗粒和雾霾/沙子混合物进行了影响实验，并分析了这些样本中生命的组成部分。还分析了未受冲击的雾霾和沙粒样本，以确定生物分子浓度和分布因冲击而发生的变化。在所有样品中，我们使用空白扣除程序检测了七​​个核碱基、九个蛋白氨基酸和五个其他生物分子（例如尿素），以消除由于污染而产生的信号。我们发现 13 GPa 的冲击压力会不同程度地降解雾霾颗粒和雾霾/沙子混合物中的核碱基、氨基酸和其他一些有机物；然而，某些单个生物分子变得丰富，甚至是从这些事件中产生的。在含有沙子的撞击实验中，黄嘌呤、苏氨酸和天冬氨酸被富集或产生，这表明这些矿物质可能会催化这些生物分子的产生。另一方面，胸腺嘧啶和异亮氨酸/正亮氨酸在不含沙子的雾霾样品中富集或产生，这表明催化颗粒并不是所有冲击冲击合成所必需的。尿嘧啶、甘氨酸、脯氨酸、半胱氨酸和酪氨酸对于影响相关加工是最不稳定的。这些实验表明，撞击改变了泰坦表面的生物分子分布，并且与表面细粒材料共存的有机雾霾可能为泰坦上进一步的生命起源化学提供了最初的来源。