外媒：首次在地球外确认“生命之源”存在

据多家日媒近日报道，日本文部科学省称，科学家在小行星探测器“隼鸟2号”采集的样本中检测到了20多种氨基酸。这是第一个证明在地球外存在氨基酸的证据。

• More than 20 types of amino acids have been detected in samples Japan's Hayabusa2 space probe brought to Earth from an asteroid in late 2020, a government official said Monday, showing for the first time the organic compounds exist on asteroids in space.
• With amino acids essential for all living things to make proteins, the discovery could hold clues to understanding the origins of life, the education ministry said.

“隼鸟2号”接近小行星“龙宫” 图源：JAXA

“史无前例的发现”

2020年12月，由探测器“隼鸟2号”搭载的为期6年的回收舱从3亿多公里外的小行星“龙宫”（Ryugu）返回地球，并带回约5.4克行星表面样本（surface material）。日本宇宙航空研究开发机构（JAXA）等团队分析了样本后，从中检测到20多种氨基酸。

2019年11月，“隼鸟2号”拍摄的小行星“龙宫” 图源：JAXA

据日本共同通讯社（Kyodo News），日本横滨国立大学天体生物学名誉教授小林宪正表示，在地球以外天体上发现多种氨基酸“史无前例”，甚至可能暗示地球以外存在生命。

• Kensei Kobayashi, professor emeritus of astrobiology at Yokohama National University, said the unprecedented discovery of multiple types of amino acids on an extraterrestrial body could even hint at the existence of life outside of Earth.
• "Proving amino acids exist in the subsurface of asteroids increases the likelihood that the compounds arrived on Earth from space," he said.

他表示，这也意味着氨基酸可能存在于其他行星和天然卫星上，暗示宇宙中的生命可能诞生在比以往认知中更多的地方。

• It also means amino acids can likely be found on other planets and natural satellites, hinting that "life could have been born in more places in the universe than previously thought," Kobayashi added.

“隼鸟2号”从“龙宫”采集的样本 图源：JAXA

据《朝日新闻》，“隼鸟2号”采集样本来自不受阳光或宇宙射线侵蚀的小行星地下物质，对其分析是在没有将其暴露于地球空气中的情况下进行的，这意味着研究人员首次证实了外层空间中也存在生命的组成部分。

• Hayabusa2 was groundbreaking in that it collected subsurface materials not weathered by sunlight or cosmic rays.
• The latest analysis of the samples was conducted without exposing them to Earth's air, meaning researchers confirmed for the first time the building blocks of life also exist in outer space.

报道指出，此前学术界有说法认为，地球上的原始氨基酸分子是通过陨石带入地球的，这项研究的结果可能会进一步佐证这一假设。

• The latest discovery will likely reinforce the theory that the amino acids that exist on Earth today were brought by meteorites that rained down on the planet after it cooled.

随着对来自“龙宫”样本数据的更多分析，科学家将获得关于这颗小行星的组成和如何形成的更多信息。通过将“龙宫”样本物质的结果与从小行星“本努”（Bennu）收集的样本进行比较，科学家将更好地了解宇宙中的各种化学混合物，以及生命是如何产生的。