On 12 November 2025, the Netherlands' first military satellite, the 6U cubesat BRIK-II (2021-058F), reentered into the atmosphere after 4 years of service. I posted about the launch and the backgrounds of this experimental small satellite in 2021.
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| BRIK-II during construction. Photo: Dutch Ministry of Defense |
At TU Delft, we have been running a reentry model for BRIK-II in the open source TU Delft Astrodynamics Toolkit (Tudat). While for many weeks the prognosis from our model pointed steadily to 14 or 15 November 2025, things changed in the last few days when a strong series of geomagnetic storms developed, due to a series of strong solar flares. This (along with suspected attitude loss, causing a higher - and variable- drag area) speeded up the reentry, as can be seen by the dramatic shift in the evolution of the reentry prediction during the last few days before reentry in the diagrams below:
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| click diagrams to enlarge |
Our last estimate, based on the last available orbit from 12 November ~6:04 UTC, is that the cubesat reentered around 15:47 ± 1.9 hours UTC on November 12, 2025.
The quoted error margin might, in fact, be a bit optimistic in this case, due to the unusually rough circumstances around the time of the reentry (which included the arrival of a shockwave from a X5.1-class solar flare). A more safe guess is reentry between ~11:45 and 19:45 UTC. The last available orbit on which our final forecast is based, dates from about 10 hours before the nominal reentry time from our model.
The map below shows the nominal reentry position plus the trajectory over the one- and two-sigma uncertainty interval in the prediction:
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| click map to enlarge |
BRIK-II, named after the very first aircraft of the Royal Netherlands Air Force in 1912 ("Brik"), was a trailblazer for the Dutch Air and Space Force. It was an experimental satellite, meant to show that operating satellites was possible for the Dutch military, and was a way to gain the Dutch Air Force valuable experience with such operations. Three other, operational, satellites would follow in the next four years: the joint Dutch-Norwegian satellites Huygens and Birkeland, and a SAR satellite.
Brik-II (the name means, a.o., "brick") truely paved the way into Space for the Dutch Air and Space Force.
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| BRIK-II imaged on-orbit by me on 30 March 2023 |
(on a related note: I have started to post experimental reentry forecasts for selected objects here: https://reentry.langbroek.org)
