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| still from one of the fireball movies posted on Twitter by @Buggy__Bugler |
In the evening of 5 June 2025 around 22h local time (17h UTC), a slow profusely fragmenting fireball was seen and filmed from several cities in Kazachstan, including Astana, and Bishkek in neighbouring Kirgistan. It had all the well-known characteristics of a satellite or rocket stage reentry. Indeed, as it turns out, this was a rocket stage reentry: the reentry of the upper stage of a Chinese Zhuque-2E (ZQ-2E) rocket, 2025-103G, from a multiple satellite launch on May 17.
Unfortunately, some Russian and Ukranian language twitter accounts started to disseminate the footage with the wildly wrong suggestion that this was a failing Russian Oreshnik IRBM breaking up. This misinformation next proliferated very quickly via various social media, and later also traditional media (e.g. Newsweek). This while it is not a Russian Oreshnik missile at all, as already mentioned.
I was alerted to the event somewhat later that evening when several of my social media followers tagged me and asked me for my opinion. It didn't take me long to identify the event as a space-launch related reentry rather than a Russian missile. Indeed, the Kazachstan MoD had meanwhile also deemed it a space debris reentry, per various news outlets.
The object in question was 2025-103G (cat. nr. 64054), the Zhuque-2E (ZQ-2E) upper stage from a Chinese satellite launch on 17 May 2025 from Dongfeng (Jiuquan). The upper stage from this launch was left in an in initially 600 x 175 km, 96.1 degree inclined orbit.
The CsPOC TIP for this object's reentry available at that time (it was updated later), had forecast reentry at 5 June 2025, 15:40 UTC with an uncertainty of ± 3 hours. The Kazachstan event (~17h UTC) hence was within the reentry window. When I checked the trajectory over this full window, it showed that the object would make a south-to-north pass over eastern Kazachstan around 17:10 UTC, very close in time to the Kazachstan event (which was reportedly around 10 pm local Astana time = around 17 hr UTC). Direction of movement in the various videos of the event matched well.
Later, CSpOC published a final TIP placing the reentry at 5 June 2025 17:08 UTC ± 1 min, near 36.6 N, 73.5 E. Given the 1 minute accuracy, this is likely based on a DoD satellite observation of the reentry fireball. The TIP position is just south of Kazachstan, but a reentry is a process of several minutes duration. Moving south-to-north, the fireball created by the fragmenting space debris would move northwards, over eastern Kazachstan, in the minutes directly after this time mark. In other words, this final TIP matches the event quite well.
Below is the trajectory over the final revolution of the ZQ-2E upper stage, based on the last available TLE (epoch 25156.48638369) which dates from ~5 hours before the reentry:
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| Click map to enlarge |
I next ran a reentry model with our Delft Technical University open source Astrodynamics package Tudat. The ZQ-2E upper stage has a dry mass of approximately 5000 kg and measures 12 x 3.4 meter. Using 60% of the maximum drag area for that dimension, a value usually representing the average drag surface of a tumbling (and hence showing a variable drag surface) elongated rocket stage well, the Tudat model predicts reentry near 17:03 UTC ± 1.1 hr (remember, this is based on a 5 hour old orbit), the nominal value being well in line with the Kazachstan event and nominally within 5 minutes of the CSpOC final TIP.
Next I ran the model again adjusting the drag area slightly, via trial-and-error, such that the model would conform to the estimated start of visibility of the reentry fireball, at just below ~100 km altitude, at the time/location of the CSpOC TIP (17:08 UTC).
I get a reasonable match when I reduce the drag area to about 58% of the maximum drag area. Below is a map showing the resulting estimated reentry trajectory (movement is from south to north):
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| click map to enlarge |
When I use this Tudat-estimated reentry trajectory to generate a sky track for Astana, Kazachstan, I get this approximate sky trajectory (movement is from left to right, i.e. south to north, low through the west):
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| Click map to enlarge |
This conforms quite well to some of the video footage of the reentry (several of which show the reentry fireball pass the waxing moon), e.g.:
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| still from one of the movies posted on Twitter by @Buggy__Bugler |
The predicted sky track for Astana of course depends on how accurate our Tudat-modelled atmospheric altitudes of the reentering rocket stage are. If they in reality are a bit lower than we modelled, the trajectory will be located slightly lower in the sky (and vice versa, slightly higher if the altitudes are in reality a bit higher). It is very clear however that the general direction and location of the trajectory in the sky matches well with what was seen and filmed.
As usual, I feel some frustration about the general absence of information on camera locations and time of the footage regarding the imagery of this event distributed via various social networks. Those data are important but almost never included. These matches of observations with reentry data would get so much easier if people posting footage would include the geographic location and the time. So please people: next time you post something like this, include these important data.
This event once again also showed the failure of AI as a reliable source of information for answering questions regarding events like this (we earlier saw that with the Kosmos 482 Descent Craft reentry too). Twitter's AI "Grok" generated some profound nonsense (i.e., misinformation) when people asked it to identify the character of the event, likely partly as a result of the large amount of disinformation already doing the rounds on social media about this event.
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