想象一下，你把一个微型实验室送入深空，却发现实验从未“醒来”。这基本上就是NASA“生物哨兵”任务发生的情况。根据NASA的任务概述，这个麦片盒大小的卫星携带活体酵母飞越了月球。其目的是测试深空辐射对活细胞的影响。但酵母没有生长。
Imagine sending a tiny lab to deep space, only to learn the experiment never woke up. That’s pretty much what happened to NASA’s BioSentinel. The cereal box-sized satellite carried living yeast and flew past the Moon, according to NASA’s mission overview. The aim was to test the effects of deep-space radiation on living cells. But the yeast did not grow.
科学家为何将酵母送入深空国际空间站上的宇航员在距地球约250英里（约400公里）的轨道上运行。地球磁场保护他们免受大部分可能损伤细胞DNA并导致严重健康问题的辐射侵害。未来深入太空的机组人员可能没有这种保护。他们将暴露在更危险的辐射中，并需要厚重的屏蔽。位于加利福尼亚州硅谷的NASA艾姆斯研究中心的科学家们通过“生物哨兵”任务提前采取行动，寻找解决这一问题的方案。
Why scientists sent yeast into deep spaceAstronauts on the International Space Station orbit about 250 miles above the Earth. Earth’s magnetic field protects them from much of the radiation that can damage DNA in our cells and lead to serious health issues. Future crews venturing farther into space might not have that protection. They will be exposed to more dangerous radiation and will need heavy shielding. Scientists at NASA’s Ames Research Center in California’s Silicon Valley are making an early move with BioSentinel to find solutions for that problem.
科学家们经常研究他们非常了解的“模式生物”。在“生物哨兵”任务中，NASA选择了用于制作面包发酵的同种酵母。深空中发现的辐射会导致酵母细胞和人类细胞DNA发生双链断裂。细胞可以修复这种损伤，且酵母和人类的修复过程非常相似。发表于2020年《IEEE航空航天与电子系统杂志》上的一篇论文指出，该任务是一项新倡议的开始。该倡议旨在通过让地球生物暴露于地球磁场之外的环境，研究深空对其的影响。
Scientists often study "model organisms" that they know well. In the case of BioSentinel, NASA chose the same yeast that is used to make bread rise. The radiation found in deep space can cause double-strand breaks in DNA in yeast cells as well as human cells. Cells can repair this damage, and the repair process is quite similar in yeast and humans. A 2020 paper in IEEE Aerospace and Electronic Systems Magazine stated that this mission is the beginning of a new initiative. This initiative aimed to study the effect of deep space on Earth organisms through exposure beyond Earth’s magnetic field.
深空中的麦片盒大小实验室“生物哨兵”于2022年11月16日搭乘“阿耳忒弥斯一号”任务发射，后者是NASA太空发射系统火箭的首次飞行。它是该次搭载的10颗立方星之一。该卫星是一颗六单元航天器，重约30磅（约13.6公斤）。发射后，它飞越月球并进入环绕太阳的轨道。
A cereal box-sized lab in deep spaceBioSentinel launched on November 16, 2022, aboard Artemis I, the first flight of NASA’s Space Launch System rocket. It was one of 10 CubeSats on that ride. The satellite is a six-unit spacecraft and weighs about 30 pounds. After launch, it flew past the Moon and went into orbit around the Sun.
NASA表示，该实验旨在成为首个在环绕地球运行的空间站轨道之外进行的长期生物学实验。当卫星超出地球保护性磁场范围后，研究团队远程启动了实验。他们计划在为期6至12个月的任务期间，在不同时间点唤醒两种酵母菌株。一种菌株在自然界中很常见，另一种则难以修复自身的DNA。
NASA says it was designed to be the first long-duration biology experiment beyond the orbit of the space station, which circles Earth. The team triggered experiments remotely when the satellite was beyond the protective magnetic field of the Earth. They were going to wake up two strains of yeast at different points during a six- to twelve-month mission. One strain is common in nature.
在2020年发表的一篇IEEE论文中，该团队表示，他们计划比较正常酵母与经过基因改造、对辐射更敏感的酵母的生长和代谢情况。NASA还保留了一套备份酵母样本，以备在卫星遭遇太阳粒子事件（即来自太阳的辐射风暴）时启用。相应的对照实验在地面和辐射较低的空间站上进行。酵母为何没有生长任务的第一阶段于2022年12月开始，2023年4月结束。
The other struggles to repair its own DNA. In the 2020 IEEE paper, the team said they planned to compare the growth and metabolism of normal yeast with yeast they engineered to be more sensitive to radiation. NASA also kept a reserve set of yeast samples in reserve to activate if the satellite encountered a solar particle event, which is a radiation storm from the Sun. The matching experiments were conducted on the ground and on the space station, where radiation is lower.
生物传感器是一个旨在确定活酵母在太空中对辐射反应的微型实验室。研究团队成功将其用于四次测试，每次测试持续两周。然而，他们没有发现任何酵母生长。据NASA称，研究团队确定深空辐射并不是原因。可能的原因是，酵母在航天器发射前于地球上等待期间已经死亡。生物哨兵仍能提供什么任务并未因酵母而结束。
Why the yeast did not growPhase one of the mission started in December 2022 and ended in April 2023. The BioSensor, which is a mini laboratory designed to determine how live yeast reacts to radiation in space, was successfully used by the team in their four tests that lasted for two weeks each. However, they didn’t find any yeast growth. According to NASA, the team determined that the radiation in deep space was not the reason. The probable cause was that the yeast expired while waiting on Earth before the spacecraft launched. What BioSentinel still offersThe mission didn’t end with the yeast.
生物哨兵还携带了一个辐射探测器，用于测量照射航天器的辐射种类和剂量。NASA延长了任务期限，截至2025年11月，该航天器仍在深空中收集数据。2025年11月16日，生物哨兵迎来了连续辐射观测三周年。当时，它距离地球超过4800万英里。这一点很重要，因为NASA当时表示，科学家预计强烈的太阳活动将持续到2026年。
BioSentinel also carries a radiation detector to measure what kind of radiation hits the spacecraft, and how much. NASA extended the mission, and as of November 2025, the spacecraft was still collecting data in deep space. BioSentinel celebrated three years of continuous observations of radiation on November 16, 2025. At the time, it was more than 48 million miles from Earth. This matters because NASA said at the time that scientists expected strong solar activity to continue through 2026.
深空实测数据依然有用，因为太阳辐射事件也会对宇航员构成威胁。酵母菌实验失败了，但辐射数据仍然有效。
Actual measurements from deep space are still useful since the solar radiation events can also be a threat to astronauts. The results from the missing yeast were a bust, but the radiation data still counts.