Venus loses its last active spacecraft, as Japan declares Akatsuki orbiter dead

日本宇宙航空研究开发机构宣布 “晓” 号金星探测器终止任务，至此金星再无现役航天器在轨运行。

Humanity's last active mission at Venus is no more.

人类针对金星的最后一项现役探测任务至此宣告终结。

The Japanese Aerospace Exploration Agency (JAXA) declared its Akatsuki spacecraft dead on Tuesday (Oct. 28), more than a year after the Venus climate probe failed to respond to calls from mission control.

日本宇宙航空研究开发机构（JAXA）于 9 月 18 日宣布终止 “晓” 号金星探测器的探测任务。而早在 2024 年 4 月底，这颗金星气候探测器便已与地面控制中心失联，此次宣告终止距失联已逾一年。

"This was a mission that changed our view of our Earth-sized neighbor, and laid the path for new discoveries about what it takes to become heaven or hell," JAXA officials stated of the mission, referring to the notoriously high-pressure and high-temperature surface of Venus in comparison to Earth.

日本宇宙航空研究开发机构（JAXA）的官员在评价该任务时称：“这项探测任务彻底改变了人类对这颗与地球体积相当的邻近行星的认知，也为探索天体如何演变为宜居天堂或炼狱般的绝境开辟了全新路径。” 这番表述所指向的，正是金星那以极端高温高压著称的表面 —— 其环境与地球的宜居状态形成了鲜明反差。

JAXA noted that the Akatsuki mission produced 178 journal papers and counting, and that it tripled its 4.5-year design lifetime — even though the probe missed its first shot at orbiting Venus.

日本宇宙航空研究开发机构（JAXA）指出，“晓” 号金星探测任务已催生出 178 篇相关期刊论文，且论文数量仍在持续增加。该探测器原本的设计寿命仅为 4.5 年，最终却实现了三倍寿命的超期服役。而这一切成就的背后，藏着一段充满波折的开局 —— 探测器在 2010 年首次尝试进入金星轨道时，因主推进器故障遗憾失利。

The $300 million spacecraft, also known as the Venus Climate Orbiter, launched in 2010 and experienced a failure of its main engine along the way, missing the chance for a crucial burn to enter orbit. Incredibly, however, the mission survived long enough for a second try at orbital insertion in 2015, when Akatsuki drew close to Venus after five years of orbiting the sun.

这艘耗资 3 亿美元的探测器又名金星气候轨道飞行器，于 2010 年发射升空。不料在接近金星准备入轨的关键阶段，其主发动机突发故障，导致用于减速入轨的关键推进点火操作未能完成。但令人惊叹的是，这项探测任务竟成功维持运行，直至 2015 年迎来第二次入轨契机 —— 彼时 “晓” 号在太阳系中围绕太阳 “流浪” 飞行五年后，终于再次靠近了金星。

"With the main rocket engine damaged, the team were forced to get creative," JAXA wrote in the statement. "The spacecraft would have to attempt capture using the less powerful thrusters that were designed for the tasks of attitude control and fine adjustments. Orbit insertion had never previously been achieved with such a method, but exploration has always been about redefining the impossible."

日本宇宙航空研究开发机构在声明中写道：“由于主火箭发动机彻底损坏，团队不得不另辟蹊径寻找解决方案。这艘探测器只能尝试借助功率较小的姿控推进器完成金星轨道捕获，而这类推进器原本仅用于航天器的姿态控制与轨道微调任务。此前从未有过依靠这类推进器实现入轨的成功案例，但航天探索的意义，恰恰在于不断改写‘不可能’的边界。”

Akatsuki not only made it but persisted in its exploration of Venus for nearly a decade. JAXA announced it had lost contact with the spacecraft on May 29, 2024 after about a month of communication issues.

“晓” 号探测器不仅成功借助姿控推进器完成金星轨道捕获，更在金星轨道上持续开展探测工作近十年。日本宇宙航空研究开发机构宣布，该探测器自 2024 年 4 月底出现通信中断问题，经过约一个月的持续抢修仍未能恢复联络，最终于 2024 年 5 月 29 日确认与其彻底失联。

Akatsuki aimed to learn more about the climate of Venus, which has surface temperatures hot enough to melt lead, alongside crushing pressure that has destroyed past landing missions in minutes. As an orbiter, Akatsuki focused on the cloud bank of Venus that is about 30 to 43 miles (50 to 70 kilometers) above the surface.

“晓” 号探测器的核心任务是深入探究金星的气候特征。金星地表环境极为恶劣，表面温度高到足以熔化金属铅，其超强大气压更是极具破坏性 —— 过往人类发射的各类着陆探测器，均在着陆后数分钟内便被这种高压彻底损毁。作为一枚金星气候轨道器，“晓” 号将探测重心聚焦于金星地表上方约 30 - 43 英里（即 50 - 70 公里）处的云层区域，以此开展金星大气的专项观测。

"In this region, winds whip at speeds that approach the Shinkansen bullet trains, 60 times faster than the planet rotation — a phenomenon that is known as 'super rotation,'" JAXA wrote. While Venusian clouds whip around the planet in about four Earth days on average, Venus' extremely slow rotation means a single Venusian day lasts the equivalent of 243 days on our planet.

日本宇宙航空研究开发机构称：“在这一云层区域，金星风速极高，堪比日本新干线高速列车的行驶速度，更是达到金星自身自转速度的 60 倍 —— 这一特殊的大气现象被定义为‘超级自转’。” 尽管金星云层绕其星体一周平均仅需约 4 个地球日，但由于金星自转速度极慢，其自转一周的时间相当于 243 个地球日，也就是说一个金星日长达 243 个地球日

Akatsuki made progress in learning about super rotation. "As Akatsuki gazed steadily at the Venusian surface, researchers mapped the clouds between hundreds of images, measuring their speed as they slid around the globe," JAXA stated. "This analysis revealed that the acceleration of the clouds depended on the local solar time, suggesting that the incredible rotation speeds were being maintained by solar heating."

日本宇宙航空研究开发机构称：“在这一云层区域，金星风速极高，堪比日本新干线高速列车的行驶速度，更是达到金星自身自转速度的 60 倍 —— 这一特殊的大气现象被定义为‘超级自转’。” 尽管金星云层绕其星体一周平均仅需约 4 个地球日，但由于金星自转速度极慢，其自转一周的时间相当于 243 个地球日，也就是说一个金星日长达 243 个地球日。

The finding has implications for life beyond Earth, the agency added. Venus orbits the sun in just 225 days, a shorter duration than its rotation. This means the planet is nearly tidally locked, which would be the case if its surface perpetually had one hemisphere facing the sun (just like Earth's moon, whose near side constantly faces our planet.)

该机构补充称，这一发现对地球以外的生命存在具有重要意义。金星绕太阳公转周期仅 225 天，短于其自转周期。这意味着该行星已近乎潮汐锁定 —— 若行星表面始终有一个半球朝向太阳，便会形成这一状态（类似地球的月球，其近侧始终朝向地球）。

"Many of the extrasolar planets discovered may be in tidal lock, and there is an ongoing debate as to whether this impedes their chances of habitability," JAXA wrote. "Without a mechanism to redistribute heat, air on the nightside of a tidally locked world would freeze and cause global atmospheric collapse. However, if Venus's rapid atmosphere rotation is driven by thermal input from the star, then this could be a common mechanism that would redistribute the heat fast enough on tidally locked worlds to save their air."

日本宇宙航空研究开发机构（JAXA）指出：“已发现的众多系外行星或许处于潮汐锁定状态，而这一状态是否会影响其宜居性，相关争议至今仍在持续。”“若缺乏热量再分配机制，潮汐锁定天体的夜侧空气会冻结，进而引发全球大气坍塌。不过，倘若金星大气的快速环流是由恒星热输入驱动，那么这一机制可能普遍存在 —— 它能在潮汐锁定天体上快速 redistribution 热量，从而维持其大气稳定。”

Akatsuki initially launched with six instruments, all of which were still working when it entered the orbit of Venus in 2015. Two infrared cameras stopped working about a year after orbital insertion, but the last four instruments were believed to still be healthy when Akatsuki stopped communicating in 2024.

“晓” 号探测器（Akatsuki）发射初期搭载了六台科学仪器，2015 年进入金星轨道时，所有仪器均保持正常工作状态。其中两台红外相机在入轨约一年后停止运行，但截至 2024 年 “晓” 号中断通信时，剩余四台仪器据信仍处于良好工作状态。

The mission made some other discoveries as well, JAXA said. Scientists spotted a bow-like feature in the atmosphere that lasted for at least four Earth days, which researchers suggested was due to mountains on Venus allowing lower-atmosphere gas to move higher as a "gravity wave" to a greater extent than observed on Earth. But learning more will require new Venus missions, JAXA said.

日本宇宙航空研究开发机构（JAXA）表示，该任务还取得了其他重要发现。科学家在金星大气层中观测到一处弓形结构，其持续时间至少达四个地球日。研究人员推测，这一现象的成因是：金星表面的山脉使低层大气气体以 “重力波” 形式向高层大气运动，且其活动强度远超地球观测到的同类现象。不过 JAXA 指出，要深入探究相关机制，仍需开展新的金星探测任务。

And there are some in the planning stages. For example, NASA is working on a mission called DAVINCI, which is designed to penetrate the atmosphere, and another one called VERITAS, which will orbit the planet in search of information about its surface and interior. And the European Space Agency is developing EnVision, an orbiter that will study the atmosphere, interior and surface of Venus.

目前已有多项任务处于规划阶段。例如，美国国家航空航天局（NASA）正在推进 “达芬奇” 号（DAVINCI）任务 —— 该任务旨在穿透金星大气层；同时还在开展 “真理” 号（VERITAS）任务，其将环绕金星运行，探测行星表面及内部相关信息。欧洲空间局（ESA）则正在研发 “愿景” 号（EnVision）轨道器，该探测器将对金星的大气层、内部结构及表面特征展开综合研究。

Both DAVINCI and VERITAS, however, are at threat of losing funding in President Donald Trump's 2026 NASA budget request, which slashes agency funding by 24% and cancels dozens of science missions. What happens next is still being debated by politicians during the ongoing U.S. government shutdown that started on Oct. 1, when funding was not agreed to for the new fiscal year.

不过，“达芬奇 +” 号（DAVINCI）与 “韦里塔斯” 号（VERITAS）这两大任务，却在美国前总统唐纳德・特朗普提出的 2026 财年美国国家航空航天局（NASA）预算案中面临断供风险。该预算案计划将 NASA 的经费削减 24%，还拟取消数十项科学探测任务。而自 10 月 1 日起，美国联邦政府因新财年拨款方案未达成共识陷入停摆，目前停摆仍在持续，后续事态走向尚未有定论，政界人士对此依旧争论不休。