NASA calls off mission to rescue Swift gamma-ray observatory
NASA calls off mission to rescue Swift gamma-ray observatory
NASA 取消营救 Swift 伽马射线天文台的任务
NASA and Katalyst Space Technologies announced Wednesday they are giving up on a robotic mission to rescue the Swift gamma-ray telescope before it falls out of orbit. The rescue satellite, named Link, launched July 3 on a journey to fly up to NASA’s Neil Gehrels Swift Observatory, capture it with three robotic arms, and boost its orbit high enough to escape a looming reentry.
NASA 和 Katalyst Space Technologies 周三宣布，他们将放弃在 Swift 伽马射线望远镜坠入大气层前对其进行机器人营救的任务。这颗名为“Link”的营救卫星于 7 月 3 日发射，旨在飞往 NASA 的尼尔·格雷尔斯 Swift 天文台（Neil Gehrels Swift Observatory），利用三只机械臂将其捕获，并将其轨道提升至足够高的高度，以避免即将发生的重返大气层坠毁。
Link is about the size of a refrigerator, with two power-generating solar arrays and three xenon-fueled electric thrusters to send Swift into a safer, higher orbit. Katalyst, the startup leading the Swift rescue effort, said Wednesday that “ongoing attitude control issues” will prevent the Link satellite from completing its rescue mission. The spacecraft is still alive, and Katalyst said it will make the most of Link’s remaining capacity, which may still allow it to get near enough to Swift for a demonstration of the satellite’s close-in navigation system.
Link 卫星的大小约为一台冰箱，配备了两块发电太阳能电池阵列和三台氙燃料电推进器，旨在将 Swift 推向更安全、更高的轨道。领导此次 Swift 营救工作的初创公司 Katalyst 周三表示，“持续的姿态控制问题”将导致 Link 卫星无法完成其营救任务。目前该航天器仍然处于工作状态，Katalyst 表示将充分利用 Link 的剩余能力，这或许仍能使其靠近 Swift，从而演示该卫星的近距离导航系统。
“While the mission will not have the ending we originally intended, NASA and Katalyst are assessing what milestones remain ahead,” Katalyst said in a statement. “We will continue working to extract technical and operational value from the spacecraft.”
“虽然任务没有达到我们最初预期的结局，但 NASA 和 Katalyst 正在评估未来还有哪些里程碑可以实现，”Katalyst 在一份声明中表示。“我们将继续努力从这艘航天器中挖掘技术和运营价值。”
It was a lot to ask
这是一项艰巨的任务
The Swift rescue mission was always risky. NASA awarded Katalyst a $30 million contract less than a year ago to build and launch the Link satellite. NASA said Katalyst had to launch the rescue mission by this summer in order to reach Swift before it falls back into Earth’s atmosphere and burns up.
Swift 营救任务从一开始就充满风险。不到一年前，NASA 向 Katalyst 授予了一份 3000 万美元的合同，用于建造和发射 Link 卫星。NASA 表示，Katalyst 必须在今年夏天之前发射营救任务，以便在 Swift 坠回地球大气层并烧毁之前抵达目标。
“NASA should be willing to move quickly and take smart risks when the potential return is worth it, and that is exactly what we did with this mission,” said NASA Administrator Jared Isaacman. “This is not the outcome we were working toward, but it does not change why this mission was worth attempting.”
“当潜在的回报值得时，NASA 应该愿意快速行动并承担明智的风险，而这正是我们在这次任务中所做的，”NASA 局长贾里德·艾萨克曼（Jared Isaacman）表示。“这不是我们努力追求的结果，但这并不改变这项任务值得尝试的原因。”
NASA gave Katalyst a remarkably tight schedule. It usually takes several years to ready a first-of-its-kind satellite for launch. Katalyst did it in nine months. The timeline forced hard trade-offs, with the schedule driving engineers to tolerate technical risks they might not otherwise accept.
NASA 给 Katalyst 的时间表非常紧迫。通常情况下，准备一颗首创类型的卫星发射需要数年时间，而 Katalyst 在九个月内就完成了。这一时间表迫使团队做出了艰难的权衡，进度压力促使工程师们不得不容忍那些在其他情况下可能不会接受的技术风险。
Everything seemed to go well during the satellite’s first few weeks in orbit. That changed in late July when the Link spacecraft suddenly spun out of control. Katalyst hasn’t said what caused the problem, but two of the satellite’s three reaction wheels, used for attitude control, stopped working. There were also issues with cold gas thrusters used for finer pointing control. That left the satellite’s three low-impulse plasma thrusters as the only means of regaining control of Link’s orientation as it zipped around the Earth at nearly 5 miles per second. But it wasn’t enough.
卫星在轨道运行的最初几周一切似乎都很顺利。但到了 7 月下旬，情况发生了变化，Link 航天器突然失控旋转。Katalyst 没有说明导致该问题的原因，但卫星用于姿态控制的三台反作用轮中有两台停止了工作。此外，用于精细指向控制的冷气推进器也出现了问题。这使得卫星仅剩下三台低脉冲等离子推进器作为重新控制 Link 姿态的唯一手段，而此时它正以每秒近 5 英里的速度绕地球飞行。但这并不足以挽回局面。
“Katalyst designed, developed, and launched an experimental spacecraft to go after an ambitious mission on an aggressive timeline,” Katalyst CEO Ghonhee Lee said. “We took on this high-risk, high-reward challenge and are proud of the milestones we reached along the way. We have already learned a tremendous amount, and now our job is to turn those lessons into something durable—building a repeatable playbook to inform future rendezvous and proximity operations and satellite servicing.”
“Katalyst 设计、开发并发射了一颗实验性航天器，旨在紧迫的时间表内完成一项雄心勃勃的任务，”Katalyst 首席执行官 Ghonhee Lee 表示。“我们接受了这项高风险、高回报的挑战，并为我们在此过程中达到的里程碑感到自豪。我们已经学到了很多，现在我们的工作是将这些经验转化为持久的成果——建立一套可重复的行动手册，为未来的交会对接、近距离操作和卫星服务提供参考。”
Katalyst is one of several US companies working on satellite servicing. These kinds of missions could eventually refuel, repair, or upgrade satellites. The rendezvous sensors and robotic arms used by Katalyst are crucial technologies for future servicing missions.
Katalyst 是致力于卫星服务的几家美国公司之一。这类任务最终可以实现卫星的燃料补给、维修或升级。Katalyst 使用的交会传感器和机械臂是未来服务任务的关键技术。
“Building, testing, and operating this mission has already strengthened America’s space industry pipeline, advancing in-space servicing capabilities in completely new ways,” said Shawn Domagal-Goldman, director of NASA’s astrophysics division, which oversees the Swift Observatory. “We’re so proud of this team for: getting to the launch pad in record time, in a record-setting year for NASA astrophysics launches; its innovative problem-solving up to this point; and the dedication to the exciting capabilities this mission will attempt to demonstrate next.”
“建造、测试和运营这项任务已经加强了美国的航天工业链，以全新的方式推进了在轨服务能力，”负责 Swift 天文台的 NASA 天体物理学部主任肖恩·多马加尔-戈德曼（Shawn Domagal-Goldman）表示。“我们为这个团队感到自豪，因为他们：在 NASA 天体物理任务发射创纪录的一年里，以创纪录的时间将卫星送上发射台；在任务过程中展现了创新的问题解决能力；并致力于展示该任务接下来将尝试的令人兴奋的能力。”
While there is much to celebrate with Katalyst’s accomplishments, giving up on rescuing Swift will commit the nearly 22-year astrophysics mission to a fiery end. Swift is falling out of orbit and is expected to reenter the atmosphere later this year. Swift is an old mission that has far outlived its original two-year design, but astronomers still rely on it to detect and study gamma-ray bursts, the most powerful explosions in the known Universe.
尽管 Katalyst 的成就值得庆祝，但放弃营救 Swift 意味着这项运行了近 22 年的天体物理任务将迎来毁灭性的终结。Swift 正在脱离轨道，预计将于今年晚些时候重返大气层。Swift 是一个老牌任务，其寿命早已远超最初设计的两年，但天文学家仍依赖它来探测和研究伽马射线暴——这是已知宇宙中最强大的爆炸。
Swift’s unique combination of multi-wavelength instruments and agile pointing allows it to identify and locate gamma-ray bursts for follow-up observations by other observatories. The problem is that Swift lacks thrusters to maintain its orbit, so a rescue effort like Katalyst’s Link mission was the only way to keep the $500 million observatory going.
Swift 独特的多波段仪器组合和灵活的指向能力，使其能够识别并定位伽马射线暴，供其他天文台进行后续观测。问题在于 Swift 缺乏维持轨道的推进器，因此像 Katalyst 的 Link 任务这样的营救尝试是维持这座价值 5 亿美元的天文台继续运行的唯一途径。
“We were all hoping for more science from Swift,” Domagal-Goldman said in a statement. “But we knew the takeaways from this mission would be worthwhile either way, and we have gained so much through the series of accomplishments up to this point.”
“我们都希望从 Swift 那里获得更多的科学成果，”多马加尔-戈德曼在声明中说。“但我们知道，无论如何，从这次任务中获得的经验都是值得的，而且通过到目前为止的一系列成就，我们已经收获颇丰。”