US military ends long-running program to spot nuclear missile launches
US military ends long-running program to spot nuclear missile launches
美国军方结束了长期运行的核导弹发射监测项目
In late 1970, a Titan IIIC rocket launched from Space Launch Complex 40 at what was then called Cape Canaveral Air Force Station. It carried a top-secret payload for the US military. Much has changed in spaceflight since then. The Titan IIIC would bow out in 1982 after dozens of launches. Various Titans continued launching from Space Launch Complex 40 until 2005, at which point the US Air Force—in a competitive process hotly opposed by United Launch Alliance—turned the pad over to a small, largely unknown startup called SpaceX. And Cape Canaveral is now a “Space Force” station. But those unspecified payloads? Until last month, some of them were still flying operationally.
1970 年末，一枚“泰坦 IIIC”（Titan IIIC）火箭从当时被称为卡纳维拉尔角空军基地的 40 号航天发射复合体升空。它为美国军方携带了一枚绝密载荷。自那时起，航天飞行领域发生了翻天覆地的变化。“泰坦 IIIC”在执行了数十次发射任务后，于 1982 年退役。此后，各种型号的“泰坦”火箭继续从 40 号发射台执行任务，直到 2005 年。当时，美国空军在一场遭到联合发射联盟（ULA）强烈反对的竞争性招标中，将该发射台移交给了一家当时名不见经传的小型初创公司——SpaceX。如今，卡纳维拉尔角已成为“太空军”基地。但那些未公开的载荷呢？直到上个月，其中一些仍在执行任务。
They were looking for missile launches. The US government would later disclose that the top-secret payload that launched in November 1970 was a “Defense Support Program” satellite. The initial block of these satellites, launched from 1970 to 1973, had a mass of about 1 metric ton, and each carried about 2,000 infrared detectors. They were essentially very sensitive telescopes, and each satellite was launched into geosynchronous orbit. For a time, these were among the most important satellites flown by the US, as they served to detect the launch of a nuclear warhead at the country. As a result, the Defense Support Program would become one of the primary elements of American military space power during the Cold War.
它们的作用是监测导弹发射。美国政府后来披露，1970 年 11 月发射的那枚绝密载荷是“国防支援计划”（Defense Support Program, DSP）卫星。这批卫星的首批型号于 1970 年至 1973 年间发射，质量约为 1 公吨，每颗卫星携带约 2,000 个红外探测器。它们本质上是非常灵敏的望远镜，每颗卫星都被送入地球同步轨道。在一段时间内，这些卫星是美国发射的最重要的卫星之一，因为它们负责探测针对美国的核弹头发射。因此，“国防支援计划”成为了冷战时期美国军事太空力量的核心要素之一。
These initial satellites transformed experimental infrared observations into an operational program that continuously monitored the globe for missile launches. Initially built to identify Soviet ICBMs, they were essential for nuclear deterrence; later, they also became useful in conventional warfare, such as detecting Iraqi Scud missile launches. Over time, the military added to the constellation, improving reliability and expanding their capabilities. Each satellite ended up having more than 6,000 infrared detectors and a mass of about 2.5 tons. Satellites in the Defense Support Program kept on flying into space until 2007. One of them, DSP-16, even launched on a space shuttle (Atlantis) in 1991.
这些早期卫星将实验性的红外观测转化为一个能够持续监测全球导弹发射的作战项目。它们最初是为了识别苏联的洲际弹道导弹而建造的，对于核威慑至关重要；后来，它们在常规战争中也发挥了作用，例如探测伊拉克的“飞毛腿”导弹发射。随着时间的推移，军方不断扩充卫星星座，提高了可靠性并扩展了功能。最终，每颗卫星拥有超过 6,000 个红外探测器，质量约为 2.5 吨。“国防支援计划”的卫星一直运行到 2007 年。其中一颗卫星 DSP-16 甚至在 1991 年搭乘航天飞机（亚特兰蒂斯号）进入太空。
The program finally comes to an end. For more than 55 years, at least a handful of these satellites have been flying as silent sentinels—until last month. On Thursday, the US Space Force said that the final two surviving Defense Support Program satellites (presumably DSP-20 and DSP-22) participated in an on-orbit maneuvering exercise in early September. Independent orbital tracking showed that these satellites subsequently both raised their orbits by a few hundred kilometers, a move typically associated with disposing of them into graveyard orbits above geostationary space. The Space Force statement confirmed this marked the program’s official retirement.
该项目终于画上了句号。在超过 55 年的时间里，至少有几颗这样的卫星一直作为沉默的哨兵在太空中飞行——直到上个月。周四，美国太空军表示，最后两颗幸存的“国防支援计划”卫星（推测为 DSP-20 和 DSP-22）于 9 月初参与了一次在轨机动演习。独立的轨道跟踪显示，这两颗卫星随后都将其轨道抬升了数百公里，这一举动通常意味着将它们送入地球静止轨道上方的“墓地轨道”进行处置。太空军的声明证实，这标志着该项目正式退役。
“The DSP constellation was foundational to the defense of our nation,” said US Space Force Col. Brandon Davenport, Mission Delta 4 Commander. “These last two satellites were the culminating end to over a half century of space-based early warning. The DSP constellation ensured deterrence during the Cold War and protected our deployed warfighters from the Gulf War until their retirement last month.”
“DSP 星座是我们国家防御的基石，”美国太空军第 4 任务三角洲指挥官布兰登·达文波特（Brandon Davenport）上校表示。“最后这两颗卫星为半个多世纪的太空预警画上了圆满的句号。DSP 星座确保了冷战时期的威慑力，并从海湾战争开始一直保护着我们部署的作战人员，直到上个月退役。”
Two replacement programs. The program had a remarkable run in longevity. It began when such observations were still experimental, and satellite manufacturing largely produced bespoke spacecraft. Their launch extended across a range of rockets from various Titan rockets to the Delta IV Heavy program and even NASA’s Space Shuttle. The United States is not flying blind in the absence of the Defense Support Program, of course. In 2011, the military began launching a new generation of infrared satellites, known as the Space Based Infrared System. Because these satellites have better sensors, they can generally detect dimmer events and provide a longer warning time. More recently, the military is developing its Next-Generation Overhead Persistent Infrared satellites. The first of these satellites could launch within the next 12 months on a Vulcan rocket.
两个替代项目。该项目在寿命方面表现卓越。它始于此类观测尚处于实验阶段的时期，当时的卫星制造大多是定制化的。它们的发射任务涵盖了从各种“泰坦”火箭到“德尔塔 IV 重型”火箭，甚至是 NASA 航天飞机的多种运载工具。当然，在“国防支援计划”结束后，美国并不会陷入“盲区”。2011 年，军方开始发射新一代红外卫星，即“天基红外系统”（Space Based Infrared System）。由于这些卫星拥有更先进的传感器，它们通常能探测到更微弱的事件，并提供更长的预警时间。最近，军方正在开发“下一代天基持续红外”（Next-Generation Overhead Persistent Infrared）卫星。首颗此类卫星可能会在未来 12 个月内由“火神”（Vulcan）火箭发射升空。