Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA.
Astrobiology. 2010 Apr;10(3):337-47. doi: 10.1089/ast.2009.0402.
Titan organic haze analogues, or "tholins," produce biomolecules when hydrolyzed at low temperature over long timescales. By using a combination of high-resolution mass spectroscopy and tandem mass spectrometry fragmentation techniques, four amino acids were identified in a tholin sample that had been hydrolyzed in a 13 wt % ammonia-water solution at 253 + or - 1 K and 293 + or - 1 K for 1 year. These four species have been assigned as the amino acids asparagine, aspartic acid, glutamine, and glutamic acid. This represents the first detection of biologically relevant molecules created under conditions thought to be similar to those found in impact melt pools and cryolavas on Titan, which are at a stage of chemical evolution not unlike the "primordial soup" of the early Earth. Future missions to Titan should therefore carry instrumentation capable of, but certainly not limited to, detecting amino acids and other prebiotic molecules on Titan's surface.
泰坦有机霾类似物,或“索林”,在低温下长时间水解时会产生生物分子。通过使用高分辨率质谱和串联质谱碎裂技术的组合,在 13wt%氨水溶液中于 253±1 K 和 293±1 K 水解 1 年的索林样品中鉴定出了四种氨基酸。这四种物质被指定为天冬酰胺、天冬氨酸、谷氨酰胺和谷氨酸。这是首次在被认为类似于土卫六撞击熔体池和低温熔岩的条件下,检测到具有生物相关性的分子,这些条件与早期地球的“原始汤”类似。未来的土卫六任务因此应该携带能够探测到土卫六表面的氨基酸和其他前生物分子的仪器,但肯定不仅限于此。