[UPDATED] Identifying a reentry over the Canary Islands on 16 October as the reentry of the Chinese satellite Xinjishu Yanzheng 7 (XJY-7)

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In the early local morning of 16 October 2025 around 1:56 UTC, a spectacular phenomena appeared in the sky over Tenerife in the Canary Islands. A bright, slow, fragmenting fireball moved from south to north over the sky. Sonic booms were heard and registered by several seismic stations on Tenerife. The event clearly was a reentry of artificial space debris. For footage, see here and here. The all-sky image on the left above is from the Izana Atmospheric Research Center on Tenerife (the plotted sky map on the right is by me, for comparison, see discussion below).

I was alerted to the event by my Spanish colleague Josep Trigo (ICE-CSIC/IEEC) in the morning of October 16, who asked if I could identify which object was reentering here. A check on the CSpOC portal Space-Track did not yield a TIP that would match - as it turns out, the object in question never received a TIP, which is odd as it was heavy and large, as we will see.

So in order to identify it, I had to do some additional research. I selected all orbits from the orbital catalogue with perigee below 200 km. Next, I used SatEvo software to see which of these orbits would have a predicted reentry on October 15-16. From the handfull of candidates left, I next checked which of them would be over the Canary Islands near the time of the event (1:56 - 1:57 UTC on 16 October 2025). One object stood out - and it was one for which no TIP had been issued: the Chinese satellite Xinjishu Yanzheng 7 (XJY-7, 2020-102C), launched in 2020.

All sky imagery showing the reentry trail in the sky against a starry background had meanwhile been published on Twitter by the Izana Atmospheric Research Center on Tenerife. The general location of the trail amidst the stars in the sky and the direction of movement matched those expected for XJY-7 well. It was clear we had found our culprit.

Not much is known about XJY-7. Jonathan McDowell lists bus dimensions of about 3 x 5 x 9 meter and a dry mass near 3000 kg for this object in his catalogue. ESA's DISCOS lists similar dimensions but a mass of 5000 kg (perhaps a wet mass).

The last available orbit for XJY-7 was for epoch 25288.77158679, or 15 October 18:31 UTC, some 7h 25m before the event. To investigate further, I used the reentry model that my colleague Dominic Dirkx and I made some time ago (see earlier posts) in the Open Source Delft University of Technology Astrodynamics Toolkit (Tudat) to see whether I, with trial-and-error, could get a reentry model for XJY-7 to end over the Canary Islands. As it turns out, I could, for a mass of 2717 kg (close to 3 tons) and a drag area of 37.44 m² (the maximum drag surface listed by DISCOS), using past and current space weather.

The map below shows the resulting reentry groundtrack and times for this model integration. Note that the model does not take fragmentation and mass loss into account, so it has limitations and is an approximation only. I had the model terminate at 20 km altitude.

The figure below the map, compares the sky trajectory resulting from this model for the location of the Izana Atmospheric Research Center, to that registered by the all sky camera at Izana. They match well.

Click map to enlarge

 

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It is curious that no TIP was issued for this reentry by CSpOC. This was a large heavy object: 3 x 5 x 9 meter and 3 tons in mass. CSpOC apparently overlooked this reentry - a few hours post reentry, they however did add an administrative "decay message" for October 16 to the catalogue for this object, but without any further details. 

We recently have seen a complete lack of TIP's being issued for any object, for over a month. Only recently, CSpOC resumed issuing TIP's. CSpOC is currently clearly having some issues with their system. Luckily, we were nevertheless able to identify the object responsible for this spectacular reentry, by some diligent analysis.

 

UPDATE 17 Oct 2025  22:00 UTC:

Click map to enlarge (map updated to correct typo)

I played a little bit more with the reentry model, tinkering the area to mass ratio to get an even better fit to the sky trajectory as seen from the Izana camera station. Here is an updated plot of the modelled sky trajectory (numbers next to trajectory are atmospheric altitudes in km according to the simulation):

A mass of 2715.5 kg creates a very good fit, except for the end of the trail. That is no surprise: the reentry model is a simple model without mass loss and fragmentation, while in reality there is massive mass loss and fragmentation (meaning: changing area to mass ratio's for various fragments). When solid parts survive, heavy relative to their size, these have a lower area to mass ratio meaning they lose altitude less quickly.

Here is the improved model trajectory overlayed on the Izana camera image:

Click image to enlarge

(I thank Josep Trigo (ICE-CSIC/IEEC) and the Spanish SPMN for data and discussions)