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Yesterday (2024-05-02) at night I saw a SpaceX rocket from my home in Lithuania (Europe) for the second time in my life. It was Falcon 9 second stage carrying two "Maxar" satellites launched from Vandenberg Space Force Base. It looked like a small galaxy slowly moving across the northern part of the sky.

But I couldn't find an answer as to why it was visible thousands of kilometers away in Europe. I follow some telegram channels and people over in Ukraine also noticed it.

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    $\begingroup$ To clarify some doubts, can you provide us with some more information? Roughly where in Europe have you been? (Cape can Vincent will generate another answer than north cape) In which direction have you looked at what time? And maybe describe how you imagine a "small galaxy slowly moving across the sky" looks like? $\endgroup$
    – CallMeTom
    Commented May 3 at 11:48
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    $\begingroup$ @CallMeTom - assuming they are referring to what an actual galaxy looks like to the naked eye, that sounds like maybe an on-orbit burn. Whether that's what they saw and whether it was Falcon 9 is unknown. $\endgroup$ Commented May 3 at 13:52
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    $\begingroup$ It looks like sunset in Lithuania is currently around 9 pm. Yesterday's Vandenberg launch was at 18:36 GMT which would be 9:36 pm EEST. You would have to look at ground tracks of the launch to see if the Falcon 9 second stage or its recently released satellites did in fact pass overhead at the time that you saw whatever it is that you saw. $\endgroup$ Commented May 3 at 13:58
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    $\begingroup$ Newsweek article of similar phenomenon from earlier launch as it was seen over Norway. newsweek.com/spiral-sky-spacex-rocket-launch-1876397 $\endgroup$
    – BowlOfRed
    Commented May 3 at 23:25
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    $\begingroup$ @OscarBravo - launches from Cape Canaveral reach orbit long before they get anywhere near Europe. For some perspective Starlink launches towards the southeast don't even make it past the Virgin Islands by the time the second stage engine cuts off. Even more so for a Vandenberg launch. So the OP was correct in their assumption that a Falcon 9 launch cannot be seen from Europe. However on-orbit engine burns including deorbit burns certainly can be seen there. I suppose a case could be made that an on-orbit engine restart for satellite positioning is part of a launch but that gets into semantics. $\endgroup$ Commented May 4 at 17:56

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Although you probably did see Falcon 9 it would not have been the launch itself but more likely the second stage deorbit burn which occurred after the Maxar WorldView Legion satellites were deployed. That's a hard thing to confirm with limited information, but I will go through some evidence that this is what you probably saw.

First of all your intuition is correct that you are not able to see Falcon 9 launches from Europe. For example when Falcon 9 launches from Cape Canaveral, SECO (second stage engine cut-off) occurs while the rocket is still over the Atlantic Ocean and still much closer to the U.S. than to Europe. This is when the launch vehicle and its payload reaches orbit, or at least an initial orbit. When launching from Vandenberg, SECO occurs over the Pacific Ocean even farther from Europe.

The SpaceX livestream for the WorldView Legion launch did not display a ground track like they often do, but this map of the exclusion zone for the launch indicates the direction that the rocket traveled as it left Vandenberg:

Maxar launch exclusion zone



A SpaceX graphic from the webcast of the recent USSF-62 launch from Vandenberg on April 11, 2024 with a similar trajectory shows an example of where SECO occurs. As you can see it is still relatively close to the U.S. when it reaches orbit:

USSF-62 trajectory
USSF-62 trajectory (SpaceX)

However whereas the initial launch to orbit can only be seen from a few hundred kilometers from the launch site, on-orbit burns including deorbit burns can be seen from any location in the world where they happen to take place.

Ground tracks for short-lived second stages are not usually available, or at least not easily obtained, however we can look at the ground track for the WorldView Legion satellites after their release and see that in fact they passed nearly directly over Vilnius at 10:55 pm local time (EEST) which was 80 minutes after the liftoff from Vandenberg.

Maxar ground track
WorldView Legion ground track (Heavens Above)

You didn't mention a time, but is this about when you saw the "slowly moving small galaxy"? If so there was a video posted by someone in Poland at nearly exactly the same time (9:55 pm CEST) showing the Falcon 9 second stage deorbit burn:

Falcon 9 deorbit burn Poland


Poland view zoomed in

The video is a time lapse so it appears to be moving faster in the video than it actually appeared. If this is similar to what you saw, and if you saw it at this time, then it's almost certain that the slow moving glowing cloud that you saw was the Falcon 9 second stage deorbit burn.

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    $\begingroup$ Thank you for the detailed explanation. Indeed this was a correct time and image. $\endgroup$
    – Ernis
    Commented May 5 at 7:54
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When a satellite is launched, it goes into an orbit, generally a circle or an ellipse. That orbit is centered on earth's center of gravity. One point on that orbit has to be fairly close to the launch site. It looks like another point of orbit is visible from your location. Or maybe you saw the satellites on their next orbit (~90 minutes later, so the orbit track moves 1500 km to the West compared to a point on the equator).

So you weren't seeing satellites thousands of km away, they were more or less directly overhead.

The date indicates we're looking at the first WorldView Legion launch.

Successful launch 2 May 2024 at 18:30 UTC (11:36 am PDT) from SLC-4E at Vandenberg. First two Legion satellites delivered to 520-km, 97.6deg SSO with 10:30 LTDN. Falcon 9 first stage 1061-20 landed at LZ-4.

So they were launched into a sun-synchronous orbit from Vandenberg (coordinates 34.7431/-120.5144).

You're in Lithuania, around 55N/23° E. I think you saw the satellites after a few orbits. The first orbit would put them over ~60° E.

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    $\begingroup$ Re "So you weren't seeing satellites thousands of km away": I read the question as meaning Lithuania is thousands of km away from the launch site (and presumably from where the rocket stage should already have burnt out) $\endgroup$ Commented May 4 at 21:56

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