Asteroid Bennu Holds the Building Blocks of Life
Video Credit: Data: NASA, SVS, U. Arizona, CSA, York U., MDA; Visualizer: Kel Elkins (lead, SVS); Text:
Explanation: What can a space rock tell us about life on Earth? NASA‘s OSIRIS-REx spacecraft made a careful approach to the near-Earth asteroid 101955 Bennu in October of 2020 to collect surface samples. In September 2023, the robotic spaceship returned these samples to Earth. A recent analysis has shown, surprisingly, that the samples contained 14 out of the 20 known amino acids that are the essential building blocks of life. The presence of the amino acids re-introduces a big question: Could life have originated in space? However, the protein building blocks themselves held another surprise — they contained an even mixture of left-handed and right-handed amino acids — in contrast to our Earth which only has left-handed ones. This raises another big question: Why does life on Earth have only left-handed amino acids? Research on this is sure to continue.
Tomorrow’s picture: interstellar dust clouds
小行星贝努拥有生命的构件
影片提供: 数据: NASA, SVS, U. Arizona, CSA, York U., MDA; 视象化: Kel Elkins (lead, SVS); 文稿:
说明: 太空岩石能告诉我们那些地球的生命故事？美国国家航空航天局的OSIRIS-Rex太空船，于2020年10月成功轻触近地小行星贝努（101955 Bennu），并收集了它的表面样本。这些样本于2023年9月送返地球并经过分析后，意外发现样本含有现知生命的20种基本氨基酸构件中的14种。此发现再次触发了大哉问：生命是否起源于太空？此外，这些蛋白质构件，更带来了另一个出乎意料的发现—— 样本所含的左旋与右旋氨基酸之比例相同，明显有别于地球上的生命只有左旋氨基酸。于是，这又带来另一个谜团：为何地球生命只含左旋胺基酸？相关的研究，将来无疑会持续进行。
明日的图片: dust clouds
