A Falcon 9 rocket will hit the Moon this summer at seven times the speed of sound

一枚猎鹰9号火箭将于今年夏天以七倍音速撞击月球

Astronomers say the upper stage of a Falcon 9 rocket that launched in early 2025 will strike the Moon later this summer, likely on the near side of the Moon. Bill Gray, who writes the widely used Project Pluto software to track near-Earth objects, has published a comprehensive report on the impact expected to occur at 2:44 am ET (06:44 UTC) on August 5. 天文学家表示，一枚于2025年初发射的猎鹰9号火箭的二级箭体将于今年夏末撞击月球，撞击点很可能位于月球正面。开发了广泛用于追踪近地天体软件“Project Pluto”的比尔·格雷（Bill Gray）发布了一份详尽报告，预计撞击将发生在美东时间8月5日凌晨2:44（协调世界时06:44）。

The Falcon 9 rocket’s upper stage is 13.8 meters (45 feet) tall and has a 3.7-meter (12 feet) diameter. Since the Moon has no atmosphere, it will strike the lunar surface intact. Although the Moon will be visible to the eastern half of the US and Canada, and in much of South America, Gray said he believes the impact will probably be too faint to be seen by Earth-based telescopes. 这枚猎鹰9号火箭的二级箭体高13.8米（45英尺），直径为3.7米（12英尺）。由于月球没有大气层，它将完整地撞击月球表面。尽管美国和加拿大东部以及南美洲大部分地区届时可以看到月球，但格雷认为，此次撞击产生的现象可能过于微弱，地球上的望远镜无法观测到。

Highly confident in its origin

对其来源高度确信

Gray said he and other astronomers are highly confident that this object is the second stage of the Falcon 9 rocket that launched two lunar landers, Firefly’s Blue Ghost and ispace’s Hakuto-R, on January 15, 2025. After the launch, the two landers, a payload fairing, and the upper stage were all tracked following their separation. The two landers reached the Moon (only Blue Ghost successfully touched down), and the fairing reentered Earth’s atmosphere. 格雷表示，他和其它天文学家高度确信，该物体正是2025年1月15日发射两台月球着陆器（萤火虫航空公司的“蓝鬼”和ispace公司的“白兔-R”）的猎鹰9号火箭的二级箭体。发射后，两台着陆器、有效载荷整流罩以及二级箭体在分离后均受到了追踪。两台着陆器均抵达了月球（仅“蓝鬼”成功着陆），而整流罩则重新进入了地球大气层。

“The upper stage, 2025-010D, also kept orbiting the Earth, but was a bit higher and didn’t re-enter,” Gray wrote. “It’s had a few close passes by the Moon and Earth, but nothing that was close enough to look like a possible impact. The asteroid surveys observed it whenever it wasn’t too close to the Sun or Moon to see. As of 2026 February 26, we had accumulated 1053 observations of it.” “二级箭体（编号2025-010D）也一直在绕地球飞行，但轨道高度稍高，因此没有再入大气层，”格雷写道。“它曾几次近距离掠过月球和地球，但都没有近到足以构成潜在撞击的程度。只要它不处于太阳或月球附近导致无法观测，小行星巡天项目就会对其进行观测。截至2026年2月26日，我们已经积累了1053次观测记录。”

Gray estimates the object will be traveling at 2.43 km a second, or 5,400 mph, when it strikes the Moon in or near the Einstein Crater. This is about seven times the speed of sound. It will create a small crater, but otherwise should do no damage. 格雷估计，当该物体在爱因斯坦陨石坑内或附近撞击月球时，其速度将达到每秒2.43公里（约合每小时5400英里）。这大约是音速的七倍。它会撞出一个小陨石坑，但除此之外不会造成任何破坏。

Not the first time this has happened

这并非首次发生

Four years ago, Ars reported that astronomers believed another Falcon 9 upper stage would strike the Moon. However, subsequent analysis revealed that the object was, in fact, an upper stage from the Chinese Chang’e 5-T1 mission. Gray said there is no doubt that this object is the Falcon 9 upper stage because it has been tracked since launch. 四年前，Ars曾报道称天文学家认为另一枚猎鹰9号的二级箭体将撞击月球。然而，随后的分析显示，该物体实际上是中国嫦娥五号T1任务的二级箭体。格雷表示，毫无疑问，这次的物体就是猎鹰9号的二级箭体，因为它自发射以来一直处于追踪之中。

There is no risk from its impact to anything on the Moon. It is a dead world, and there are no human-landed objects nearby. However, both NASA and China are deep in the planning stages for establishing semi-permanent outposts near the South Pole of the Moon. As part of that, the cadence of launches on Falcon 9 and other rockets to the Moon is likely to increase by something like a factor of 10 due to the need to land rovers, supplies, habitats, communications equipment, and much more to support human activities. 此次撞击对月球上的任何事物都没有风险。月球是一个死寂的世界，附近也没有人类着陆的物体。然而，美国国家航空航天局（NASA）和中国都在深入规划在月球南极附近建立半永久性前哨站。作为该计划的一部分，由于需要运送月球车、补给品、栖息地、通信设备以及更多支持人类活动的物资，猎鹰9号及其它火箭前往月球的发射频率可能会增加约10倍。

There is a relatively easy fix for this: With some extra planning and sparing a little fuel, launch companies can put these stages into “disposal” orbits around the Sun and in a path that will avoid hitting Earth or the Moon in perpetuity. For the safety of future operations on the Moon, this probably should become standard operating procedure. 对此有一个相对简单的解决方法：通过额外的规划并预留少量燃料，发射公司可以将这些箭体送入绕太阳运行的“处置”轨道，使其路径永远避开地球或月球。为了未来月球作业的安全，这或许应该成为标准操作程序。